Clustering and High Availability
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Introduction to Failover Clustering (Level 100)
Presenter: Symon Perriman, Program Manager, Clustering & HA
Air Date: March 18th | Air Time: 10am-11am PST
http://msevents.microsoft.com/CUI/EventDetail.aspx?EventID=1032407190&Culture=en-US
Overview: High availability, disaster recovery, fault tolerance. If these words are not in your IT department's vocabulary, your organization is probably unprepared to deal with the inevitable—server downtime. Attend this webcast to learn about Windows Server 2008 R2 failover clustering, a high-availability solution from Microsoft. Failover clustering connects servers and monitors the health of the servers and the applications running on servers. In the event of a server failure, applications can fail over to another server and continue running with minimal interruption to your mission-critical applications. We cover the basics of failover clustering in this webcast, and we provide the information to help you get a failover cluster configured and deployed in a matter of hours.
High Availability Basics with Windows Server 2008 R2 Hyper-V (Level 200)
Presenter: Steven Ekren, Senior Program Manager, Clustering & HA
Air Date: March 19th | Air Time: 10am-11am PST
http://msevents.microsoft.com/CUI/EventDetail.aspx?EventID=1032407222&Culture=en-US
Overview: Virtualization is a hot topic on customers' minds. But what happens if you consolidate a number of servers into virtual machines, put them on a single host computer, and that computer fails? All your eggs are in one basket, so to speak, and users may not be able to access critical information. To avoid scenarios like this, high availability has become part of the virtualization discussion for organizations of all sizes, not just large Fortune 500 companies. Be sure you have the necessary knowledge to discuss high availability and virtualization with your customers. If you are new to failover clustering, this webcast is for you. We provide step-by-step instruction on configuring a highly available virtualization solution with Windows Server 2008 R2 Hyper-V and failover clustering features.
Failover Clustering Feature Roadmap for Windows Server 2008 R2 (Level 300)
Presenter: Elden Christensen, Senior Program Manager Lead, Clustering & HA
Air Date: March 26th | Air Time: 10am-11am PST
http://msevents.microsoft.com/CUI/EventDetail.aspx?EventID=1032407235&Culture=en-US
Overview: Come and learn about all the new Failover Clustering enhancements that are going to be delivered in Windows Server 2008 R2 code name "Windows Server 7" operating system. In this webcast, we drill into incremental improvements from Windows Server 2008 to the cluster validation tool, Windows PowerShell support, the new cluster configuration program, and other exciting features.
Innovating High Availability with Cluster Shared Volumes (Level 300)
Presenter: Steven Ekren, Senior Program Manager, Clustering & HA
Air Date: April 2nd | Air Time: 10am-11am PST
http://msevents.microsoft.com/CUI/EventDetail.aspx?EventID=1032407238&Culture=en-US
Overview: In this webcast, we provide an overview of the new Cluster Shared Volumes code name "Centipede" failover clustering feature in the Windows Server 2008 R2 code name "Windows Server 7" operating system. Join us to learn how the Windows Server cluster storage architecture is innovating to enable Hyper-V virtualization technology, a new and significant enhancement planned for "Windows Server 7" that is creating a lot of excitement. This is a session you don't want to miss.
Multi-Site Clustering with Windows Server 2008 Enterprise (Level 300)
Presenter: Ahmed Bisht, Senior Program Manager, Clustering & HA
Air Date: April 9th | Air Time: 10am-11am PST
http://msevents.microsoft.com/CUI/EventDetail.aspx?EventID=1032407242&Culture=en-US
Overview: As the Windows Server operating system becomes more accepted in large-scale, high-end, mission-critical IT environments, the requirements for disaster tolerance and business continuance become more and more important. In this webcast, we discuss how you can build a fault-tolerant, high-availability server solution with Windows Server 2008 failover clustering that also facilitates disaster recovery.
Network Load Balancing (NLB) and Virtual Machines
Hi,
A lot of people have asked about setting up NLB clusters on virtual machines. This is possible. But, there a few things to keep in mind.
If you’re trying to create NLB clusters using Virtual Server Virtual Machines, before designing your solution familiarize yourself with the supported configurations. Refer to http://support.microsoft.com/kb/925476 for details on which configurations are supported.
If you’re trying to create NLB clusters using Hyper-V Virtual Machines with Windows Server 2008 RTM (not R2) host(s), there are a few things to be aware of (more details at http://support.microsoft.com/kb/953828):
1- Apply the fix in the KB article to each of the Windows Server 2008 VM guests that are cluster nodes. Note that this fix will be included in Windows Server 2008 SP2.
2- NLB changes the MAC address of the machine when you bind NLB on a node, change the operation mode of the cluster, change the primary IP of the cluster, or unbind NLB from the node. Hyper-V in Windows Server 2008 requires a reboot of the VM if its MAC address is changed. The KB article describes the process to follow to create a new cluster or add nodes to a cluster using Hyper-V VMs.
If you’re trying to create NLB clusters using Hyper-V Virtual Machines with Windows Server 2008 R2 host(s), enable MAC spoofing for the virtual network used by NLB in the guests. This can be done from the Network Adapter settings on each VM that is participating in a cluster as a node. You can create NLB clusters, add nodes, and update NLB cluster configurations without having to reboot the VMs at all. Note that you will need to apply the fix at http://support.microsoft.com/kb/953828 (or use SP2) in each of the Windows Server 2008 (not R2) VM guests that are cluster nodes. But, if all your guests are Windows Server 2008 R2 or Windows Server 2008 SP2, you do not need to apply the fix.
Regards,
Ahmed Bisht
Senior Program Manager
Clustering & High-Availability
Cluster Shared Volumes (CSV): Disk Ownership
Hi cluster fans,
In Windows Server 2008 R2 Failover Clustering we have incorporated a significant architectural innovation called Cluster Shared Volumes (CSV), which functions as a distributed-access file system optimized for Hyper-V. This means that any node in a cluster can access the shared storage and any node can host VMs, regardless of which node “owns” the storage. This behavior was not included in Windows Server 2008 and this blog will discuss CSV in more detail. For information about configuring and deploying CSV, please check out this guide and be sure to send us your feedback!
Disk Ownership in 2008 and Earlier
In Windows Server 2008 and earlier, one of the required resources for each resource group was a “physical disk resource”. Basically this physical disk resource managed the cluster’s access to the application’s data on the shared storage device. This was to ensure that, at most, one node could access the data at any time to avoid corruption of the data on the LUN. If you had multiple nodes writing data to that same disk at the same time you would risk corruption. In Windows Server 2008, ownership of disks was determined by a SCSI SPC-3 protocol called ‘Persistent Reservations’ (PRs). When one node “owned” a disk, it would place a reservation on that volume. If another node tried to access this disk, it would ask for ownership of the PR, which would either be granted or denied by the node which currently owned the reservation. If another node was given ownership of the PR, the physical disk resource would fail over to that node and that node would begin managing access to the LUN. For more information about storage management and Persistent Reservations, check out these webcasts: TechNet Webcast: Failover Clustering and Quorum in Windows Server 2008 Enterprise Storage & Microsoft Webcast: Reducing IT Overhead with Windows Server 2008 Storage Features.
Since only one node could own the LUN at any time, this meant that the LUN became the smallest unit of failover. If any application running on the LUN needed to move to another node, it meant that all applications on that LUN would also be failed over (and have some downtime during that failover). This often meant that customers would want to run a single application in each LUN so that only one application would become unavailable during a failover. However, this added a lot of complexity to storage management, and we saw clusters with hundreds of resources needing hundreds of LUNs which was challenging to deploy and manage. It also meant that the required ‘Validate a Configuration…’ test took a long time as every LUN is tested against every node, so the duration scaled-up exponentially as more LUNs were added. So let’s take a look at how Cluster Shared Volumes solves these problems when you are clustering Virtual Machines…
Disk Ownership in R2 with CSV
Clustered Shared Volumes allows nodes to share access to storage, which means that the applications on that piece of storage can run on any node, or on different nodes, at any time. CSV breaks the dependency between application resources (the VMs) and disk resources (for CSV disks) so that in a CSV environment it does not matter where the disk is mounted because it will appear local to all nodes in the cluster. CSV manages storage access differently than regular clustered disks and we are going to introduce the concept of the “Coordinator Node”, which is the node which “owns” the storage and manages the access of other nodes to that piece of storage.
The Coordinator Node can be any node in a cluster (let’s say Node1), and the VMs on that CSV disk can also be on any node in that cluster (let’s say on Node2). Whenever the application running in the VM needs to write data to the CSV disk, it is going to ask the Coordinator Node for permission. Depending on whether the data being written requires changing the file system structure, the Coordinator Node will do one of two things. It will either send Node2 the addresses of the writable blocks in the file system, which the VM will directly write to (so Node2 directly accesses the LUN). Or, the Coordinator Node will write that data to the disk, which is done if the Coordinator Node must manage the file system itself, for example when it extends, moves or changes the attributes of a file. The Coordinator Node ensures that access to the NTFS file system (required for CSV) is controlled in order to prevent corruption.
If you have multiple CSV volumes, then you will have multiple Coordinator Nodes in your cluster. Each CSV disk has one node that is its Coordinator Node, but that same node does not have to be the Coordinator Node for all CSV disks in the cluster. While these multiple Coordinator Nodes could be the same physical node, we recommend that you try to distribute them across your cluster to reduce network traffic overhead on a single node. We will look at how the Coordinator Node manages data and traffic in a later blog post.
CSV gives you the ability to store your VHDs on a single LUN and run the VMs anywhere in the cluster (pass-through disks are not supported when using CSV). This will make your cluster quicker to configure and easier to manage. Additionally, CSV enables Live Migration which allows you to move a running VM from one node to another node with zero downtime. Since disk ownership no longer needs to change when a VM moves to another node, this makes the process quicker and safer, allowing clients to remain connected while the virtual machine is moved to another node in the cluster. Live migration using CSV will be explored in detail in another blog post.
But what about failures? Do not worry! CSV is resilient to failures including the loss of the Coordinator Node, the node hosting the VM, the loss of a network path and the loss of a connection to the storage. The cluster will stay up and running with little or no downtime. CSV failure resiliency will also be addressed in a future blog post.
CSV sounds great…but how much is this going to cost me?
NOTHING! That’s right – Cluster Shared Volumes comes as a standard feature with Failover Clustering in the Windows Server 2008 R2 Enterprise & Datacenter Editions and in the Microsoft Hyper-V Server R2 Edition.
While CSV could be compared to a Clustered File System (CFS), it is different in that it does not use any proprietary technology – it uses standard NTFS, so there is nothing special you need to purchase or support – it just works! You can continue to use your regular clustering storage devices – Fibre Channel, iSCSI or Serial Attached SCSI – so long as they receive a logo for R2 and the complete solution passes the “Validate a Configuration…” tests.
However, it is important to remember that in its initial release, CSV will only support highly-available Hyper-V Virtual Machines in the host partition. Of course, you can still run any service or application within that virtual machine, so long as it is supported running in a virtualized environment (KB: Supported Virtualization Environments).
Please try out the Beta version of Windows Server 2008 R2 Failover clustering with Cluster Shared Volumes (CSV) and live migration, available here: http://www.microsoft.com/windowsserver2008/en/us/R2-Beta.aspx. For information about configuring and deploying CSV, check out this guide. Please report any bugs through the built-in ‘Send Feedback’ tool or the Microsoft Connect site, or send us your comments by clicking the ‘Email’ link in the upper-left corner of this site.
Thanks,
Symon Perriman
Program Manager
Clustering & High-Availability
What the heck is PlumbAllCrossSubnetRoutes?
Hi cluster fans,
If you ever browsed your cluster properties you may have noticed an entry for “PlumbAllCrossSubnetRoutes” and you’ve probably asked yourself, “what the heck is that?”
The only thing on the web will point you to MSDN (http://msdn.microsoft.com/en-us/library/aa371422(VS.85).aspx) but there’s not a whole lot of info here:
PlumbAllCrossSubnetRoutes
Data type: uint32
Access type: Read/write
Plumbs all possible cross subnet routes to all nodes.
Windows Server 2003:
This property is not supported.
So let’s take a look at this in a little more detail and explain exactly what this does…
First of all, this is a property which is only exposed through the command line interface. If you run CMD as an administrator, you can see the cluster properties using > cluster /prop.
Here you will find the PlumbAllCrossSubnetRoutes property:
Starting in Windows Server 2008 Failover Clustering nodes can communicate with each other across a router (this is often referred to as the multi-subnet or cross-subnet support), which is very important in supporting our multi-site clustering scenarios. To do this, the cluster service builds a list of communication routes to every other node in the cluster and provides those routes to the NetFT driver, which is clustering’s fault-tolerant network driver.
Let’s assume you have a 2-node cluster. Both nodes are in the same site, and both are connected to three networks A, B, and C. Each node should end up with three routes in the NetFT driver – from Node 1’s perspective we will see: A1->A2, B1->B2, and C1->C2. But now let’s assume that networks A, B, and C are all connected to the same routing infrastructure, and thus interfaces on all networks are mutually reachable. Still, by default, each node will end up with the same three routes: A1->A2, B1->B2, and C1->C2.
But if you set the PlumbAllCrossSubnetRoutes property (to equal 1), then nodes will also attempt to find those routes that cross subnets. So Node 1 would end up with all these routes: A1->A2, B1->B2, C1->C2, A1->B2, A1->C2, B1->A2, B1->C2, C1->A2, C1->B2 – nine routes. Why is this bad? Well it uses a lot more heartbeats, especially if you have more than two nodes and more than two networks – think how quickly this could exponentially scale up. Well, why is this good? This can enable cluster communication to survive some real pathological failures. For instance, let’s say network A completely fails, and B1 fails, and C2 fails. Your cluster is still up because you have C1->B2. We didn’t think all the heartbeat and fault isolation complexity cost was worth it for most customers who are responsive to the first failure that occurs, so we left PlumbAllCrossSubnetRoutes off by default. I haven’t yet heard of a customer that experienced that pathological failure and decided to enable PlumbAllCrossSubnetRoutes, however we wanted to extend the option to our customers if they so choose.
Also, in a true multi-subnet cluster (where Node 1 and Node 2 have no subnets in common), the cluster service always searches for all cross-subnet routes, so PlumbAllCrossSubnetRoutes has no effect.
Thanks,
David Dion
Principal Development Lead
Clustering & High Availability
Deploying Cluster Shared Volumes (CSV) in Windows Server 2008 R2 Failover Clustering
Hi cluster fans,
By now you have probably heard of the new architectural innovation being brought to Failover Clustering in Windows Server 2008 R2 known as Cluster Shared Volumes, or CSV. CSV functions as a distributed-access file system optimized for Hyper-V. A comparison would be to a clustered file system, however, unlike other clustered file systems, CSV does not use any proprietary technology – it uses standard NTFS, so there is nothing special you need to purchase or support – it just works! If your storage is suitable as a standard clustered disk, it can be used as a Cluster Shared Volume. In the past, only one node could host a virtual machine (VM) and access the VHD on the shared storage, so if another node needed to host the VM or access the disk, it would need to failover and it would affect every resource on that shared disk. With CSV in R2, any node can host the VM and any node can access the VHD on shared storage, so VM and disk ownership can move freely across cluster nodes without impacting any other resources on that shared disk.
CSV will provide many benefits, including easier storage management, greater resiliency to failures, the ability to store many VMs on a single LUN and have them fail over individually, and most notably, CSV provides the infrastructure to support live migration of Hyper-V virtual machines. This blog post will cover configuring and deploying Hyper-V VMs using CSV in a Windows Server 2008 R2 Failover Cluster. We will discuss other benefits and features of CSV and live migration in future posts. All information is based on the Beta 7000 build of Windows Server 2008 R2 and is subject to change for the RTM version of this product. Please report any bugs through the Microsoft Connect site or send us feedback by clicking the ‘Email’ link in the upper-left corner of this site. Thanks,
Symon Perriman
Program Manager
Clustering & High-Availability
1) Prepare your cluster
To configure CSV we must first build the cluster. There is nothing different which needs to be done for CSV. R2 clustering will still support iSCSI, Fibre Channel and Serial Attached SCSI (SAS) for storage. CSV will work with any of these, so long as the disk is using NTFS as the file system.
For the networks, it is still recommended to have a public network for client connections and a ‘heartbeat’ network for health monitoring. Additionally, we recommend a dedicated network for CSV and live migration traffic which should be at least 1 GB. This is to ensure that the heartbeat network does not get flooded and miss health-checks which would cause a failover. If you are using iSCSI you will need another NIC for that iSCSI network.
Once you have verified that the hardware you will use in the cluster supports Hyper-V, you install the Failover Clustering feature and the Hyper-V role from Server Manager on every node in the cluster. Due to the way which CSV disks are accessed, it is recommended that you use the same drive letter for your OS on every cluster node (such as C:/).
Once the hardware is connected and the correct roles and features are installed, you should ensure that the entire clustering configuration is supported. This is done by running the built-in Validate a Configuration tool (Guide: Validating Hardware for a Failover Cluster). So long as every component in the solution has a logo for Windows Server 2008 R2 and it passes ‘Validate’ then it is supported for CSV. Alternatively, you can purchase a pre-Validated solution from one of our partners in the Failover Clustering Configuration Program.
After the solution has passed ‘Validate,’ create a cluster (Guide: Creating a Failover Cluster)
2) Enable CSV
To enable Cluster Shared Volumes (CSV) on a cluster, click on that cluster name in the navigation pane in the Failover Cluster Manager MMC snap-in. In the center pane, click the “Enable Cluster Shared Volumes…” link. A notification appears reminding you that CSV is only for use with Hyper-V. The cluster now supports CSV.
A new node appears in the navigation pane for Cluster Shared Volumes:
3) Create CSV Disks
Now that CSV is enabled, create some CSV disks.
A. Select the Cluster Shared Volumes node in the navigation pane in the Failover Cluster Manager.
B. In the right Actions pane, select “Add storage”. This will bring up a window that shows all the disks in the Available Storage group. Check the disks you want to add, then select “OK”
C. The new disk(s) now appear in the list for Cluster Shared Volumes:
4) Copy VHDs to your CSV Disks
CSV allows every cluster node to access the disk concurrently. This is accomplished by creating a common namespace under %SystemDrive%/ClusterStorage. For this reason, it is necessary to have the OS on the same drive letter on every node in the cluster (such as C:/, which will be used in this blog). You will see the same directory from every node in the cluster and this is the way to access CSV disks.
Each CSV disk has its own volume in the directory and is assigned the default name, VolumeX, for each disk. In this example we have 3 CSV disks so we see 3 folders. The C:/ClusterStorage directory must keep the same name, however the volumes within this directory can be renamed.
You will need to copy your VHDs onto these directories to create highly-available VMs. CSV will support dynamically-expanding, fixed-sized, and differencing VHDs. CSV will not support pass-through disks.
5) Create VMs on CSV Disks
After enabling CSV and placing the VHDs on the CSV disks, we are ready to make those virtual machines highly-available.
A. Open Hyper-V Manager
B. From the Action pane, select “New” and then “Virtual Machine”. This will open the New Virtual Machine Wizard.
C. Provide a name for the Virtual Machine and check-mark the box for “Store the virtual machine in a different location”, then specify the path under “C:/ClusterStorage/” for the volume that you want the VM to use.
D. Specify the memory for the VM, then “Next >”
E. Specify the network for the VM, then “Next >”
F. In the “Connect Virtual Hard Disk” page of the wizard, if you specify either “Create a virtual hard disk” or “Use and existing virtual hard disk”, specify a path to a Cluster Shared Volume under C:/ClusterStorage/
G. Select “Next >”
H. Choose the desired options in the “Installation Options” wizard page. Select “Next >”
I. Select “Finish” at the Summary Page of the Wizard
6) Make your CSV VMs Highly-Available
Now that we have created our VMs on our CSV disks, we can make them highly-available so they can be managed by the cluster and can fail over.
A. Open Failover Cluster Manager
B. In the left pane, select “Services and Application”
C. In the Action pane, select “Configure a Service or Application”. This will open the “High Availability Wizard”
D. Select “Virtual Machine”, then select “Next >”
E. Check the Virtual Machine that you want to add to the Failover Cluster. (Note, the VM must be shutdown/turned off to be added) Select “Next >”
Failover Clustering will determine if this VM is using CSV or standard cluster disks based on the path of the VHD (it will look for the %SystemDrive%/ClusterStorage path).
F. Review the Confirmation page in the wizard and select “Next >”
G. Review the Summary page in the wizard. If the status is not “Success”, review the report by selecting the “View Report...” button and investigate the information for possible causes. Otherwise, select “Finish”
The Virtual Machines will be shown in the left pane of Failover Cluster Manager. They are automatically given the Name “Virtual Machine” with a number to differentiate them. These names can be changed by right clicking on them and selecting “rename”.
Start your VMs when you are ready.
7) Perform a Live Migration
You now have your CSV cluster up and running with no special hardware or additional considerations. You can manage the Virtual Machine resource like any standard resource, such as changing properties, creating dependencies, and performing failovers. You will notice that for VMs you can now perform a live migration which allows you to move a running VM from one cluster node to another cluster node without any client disruption. This keeps a VM highly-available even when the VM moves between different physical machines.
To perform a live migration, select the ‘Live migrate this virtual machine’ button and pick a target in the right Actions pane in the Failover Cluster Manager snap-in. This will perform the live migration and its status will be indicated in the center information pane.
You can have CSV without live migration and you can perform a live migration without CSV, however, these are complementary technologies which enhance each other. We will look at the functions of each in more detail in later blog posts.
Additional Resources
· Whitepaper: Windows Server 2008 R2 & Microsoft Hyper-V Server 2008 R2 - Hyper-V Live Migration Overview & Architecture: http://www.microsoft.com/downloads/details.aspx?FamilyID=fdd083c6-3fc7-470b-8569-7e6a19fb0fdf&displaylang=en
· Step-by-Step Guide for Hyper-V: Using Live Migration in Windows Server 2008 R2:
http://technet.microsoft.com/en-us/library/dd446679.aspx
Starting your cluster nodes in Windows Server 2008
Hi cluster fans,
Many of you have asked about starting up an offline cluster in Windows Server 2008. What is the correct process? Can I start all nodes at once? Need I need to stager boot times by 30-60 seconds, as was recommended in Windows Server 2003? The short answer is that you can start all your nodes simultaneously without any issues, but let’s look at this in some more detail…
In Windows Server 2003 a node starting the cluster service would first try to join the cluster by looking for a sponsor node. If, after 30 seconds, no sponsor node was found, then the node would try to form the cluster by arbitrating for the quorum resource. Once a node determined that it was going to form the cluster, it would no longer try to join with other nodes – either it would succeed in quorum arbitration and form, or it would fail and restart the cluster service (ClusSvc) 60 seconds later. Thus, if you booted all nodes at the same time, there was a reasonable probability that they would all start looking for a sponsor at the same time. All nodes would wait for 30 seconds, and then they would all arbitrate for the quorum resource at the same time. Only one would win, and the others would need to back off and start ClusSvc again later. 60 seconds later, all of the nodes that lost quorum arbitration would all start looking for a sponsor again at the same time. They would all find the one node that formed the cluster.
However Windows Server 2003 also had the problem that join was serialized – only one node could join at a time. Especially in large clusters, the nodes that had to wait to join might timeout, so then they would terminate ClusSvc, which would lead to ClusSvc starting 120 seconds later for another join attempt. You can see that giving one node a head start allows it to search for sponsors and then arbitrate for the quorum resource with no interference. After that, if the remaining nodes are staggered by a few seconds, then there is no contention to join, and each node will find a sponsor and join as it starts ClusSvc.
In Windows Server 2008, there are three major changes the affect this behavior. First, a node does not search for sponsors for only 30 seconds. In fact, a node will continually try to establish connections to missing nodes. Because a node continually tries to contact missing nodes, there is no need to wait a full 30 seconds prior to quorum arbitration. A node starting ClusSvc that finds itself one vote below quorum will arbitrate for the quorum resource after only a few seconds. Second, a majority of nodes can form the cluster without arbitrating for the quorum resource. This means the cluster will actually form faster if all nodes start at the same time – there will be no need to arbitrate for the quorum resource, which takes an extra few seconds. Finally, the join operation is much less serialized, so multiple nodes can join the cluster practically simultaneously.
As an example, the Windows Server 2008 ‘Create a Cluster’ operation (either through the Failover Cluster Manager, ClusAPI, or cluster.exe) starts ClusSvc on all nodes at the same time, and this works just fine.
Once again, this is some great innovation from the Clustering and High Availability team to make clustering even easier.
Thanks,
David Dion
Principal Development Lead
Clustering & High Availability
Clustering Docs, Blogs & Webcasts
Hi Cluster Fans,
The cluster team has been busy working on some great new features for Failover Clustering in Windows Server 2008 R2. Meanwhile our friends have written some great blog posts which you may find interesting.
Thanks,
Symon Perriman
Program Manager
Clustering & High Availability
Whitepaper: Windows Server 2008 R2 & Microsoft Hyper-V Server 2008 R2 - Hyper-V Live Migration Overview & Architecture
http://www.microsoft.com/downloads/details.aspx?FamilyID=fdd083c6-3fc7-470b-8569-7e6a19fb0fdf&displaylang=en
One of the most highly anticipated new features in Windows Server 2008 R2 Hyper-V is live migration. This document describes the live migration feature of Windows Server 2008 R2 Hyper-V in detail, including how live migration moves running VMs and requirements for implementing live migration
Step-by-Step Guide for Hyper-V: Using Live Migration in Windows Server 2008 R2
http://technet.microsoft.com/en-us/library/dd446679.aspx
Live migration is a new Hyper-V feature in Windows Server 2008 R2, which requires the failover clustering role to be added and configured on the servers running Hyper-V. Live migration allows you to transparently move running virtual machines from one node of the failover cluster to another node in the same cluster without a dropped network connection or perceived downtime. In addition, failover clustering requires shared storage for the cluster nodes. This can include an iSCSI or Fiber-Channel Storage Area Network (SAN). All virtual machines are stored in the shared storage area, and the running virtual machine state is managed by one of the nodes.
File Share “Scoping” in Windows Server 2008 Failover Clusters
http://blogs.technet.com/askcore/archive/2009/01/09/file-share-scoping-in-windows-server-2008-failover-clusters.aspx
Implementing highly available file servers in Windows Server 2008 is very different from how it was done in previous versions of Microsoft's clustering technology. One of the new pieces of functionality implemented in highly available file servers is 'scoping' of shared folders. What this means is when a shared folder is created in a Windows Server 2008 Failover Cluster, it is not only associated with two other resources in the same resource grouping - a Client Access Point (CAP) and a File Server Resource, but it will be accessible only by way of the Network Name resource which is one of two components of a Client Access Point (CAP) (the other being an IP Address). Now, one may say, "That has been the way we have always accessed file shares in the past". This is true, but things have changed a little and that is what we will be discussing here.
Chuck Timon
Senior Support Escalation Engineer
Microsoft Enterprise Platforms Support
Configuring Auditing for a Windows Server 2008 Failover Cluster
http://blogs.technet.com/askcore/archive/2009/01/19/configuring-auditing-for-a-windows-server-2008-failover-cluster.aspx
The Windows Server 2008 Failover Clustering auditing feature has been requested by customers and provides the capability to monitor, or audit, cluster access. The cluster auditing feature can be enabled to audit accesses (Success and/or Failure) of an object. The object, in this case, will be the Microsoft Failover Cluster. This is accomplished by auditing client accesses to a cluster using Cluster APIs. This basically means that a client trying to access a cluster using either the Failover Cluster Management snap-in (Cluadmin.msc), the cluster.exe command line or any custom application that calls cluster APIs, will be subjected to auditing events if configured.
Chuck Timon
Senior Support Escalation Engineer
Microsoft Enterprise Platforms Support
Sorting out some myths and facts concerning Windows Server 2008 Failover Clustering
http://blogs.technet.com/askcore/archive/2009/01/26/sorting-out-some-myths-and-facts-concerning-windows-server-2008-failover-clustering.aspx
You may be wondering why, at this point in time, we are publishing a blog such as this. That is a good question, but the answer is rather straightforward - because even though Windows Server 2008 has been out for awhile now, we are starting to see an increase in the number of customers starting to use the Failover Clustering feature. Some of these customers are still trying to apply the concepts from previous versions of Microsoft Clustering. Doing this sometimes causes problems and we end up getting calls. In an effort to head-off some of those calls, here are some myths and facts about Windows Server 2008 Failover Clustering. We hope these will help.
Chuck Timon & John Marlin
Senior Support Escalation Engineers
Microsoft Enterprise Platforms Support
Adding a disk to a Windows 2008 Failover Cluster using cluster.exe commands
http://msmvps.com/blogs/jtoner/archive/2009/01/08/adding-a-disk-to-a-windows-2008-failover-cluster-using-cluster-exe-commands.aspx
This isn't specific to multi-site clustering, but I've certainly had to use this many times when adding devices to my multi-site clusters. In Windows 2008, Microsoft has added some new logic while adding disk resources to a cluster. In Windows 2008, when you attempt to "Add a disk" through the cluster administrator GUI, the cluster does a quick check on the available disks to ensure that the disks are present on all nodes of the cluster before presenting this as an available disk in the Cluster Administrator GUI. This can be bad for geo-clusters as the disks are unlikely read/write enabled on all sites, causing the cluster GUI to display an error message.
John Toner
Microsoft MVP – Clustering & HA
Support Technician, EMC
Webcast: Hyper-V with Windows Server 2008 R2 Live Migration
http://www.savilltech.com/Videos/LiveMigration/LiveMigration640480.wmv
See this webcast covering Live Migration with Failover Clustering on Clustered Shared Volumes in Windows Server 2008 R2.
John Savill
MVP – Clustering and HA
Principal Architect, EMC Consulting
Webcast: Cluster Shared Volumes and NetFT Traffic Deep Dive
http://www.savilltech.com/Videos/CSVDeepDive/CSVDeepDive.wmv
This webcast looks at the networking functionality and improvements made by Cluster Shared Volumes in Windows Server 2008 R2 Failover Clustering.
John Savill
MVP – Clustering and HA
Principal Architect, EMC Consulting
Webcast: Clustering in a Virtual World
http://www.savilltech.com/Videos/Clustering_in_a_virtual_world/Clustering_in_a_virtual_world.wmv
The trends and technologies behind the “Virtual Datacenter” are discussed in this webcast. This is the vision of server consolidation on highly-available virtual machines using Windows Server Failover Clustering and Hyper-V.
John Savill
MVP – Clustering and HA
Principal Architect, EMC Consulting
Webcast: Exchange 2007 High Availability Deep Dive
http://www.savilltech.com/Videos/Ex2007HA/exch2007halrg.wmv
This webcasts provides an overview of Exchange 2007 using Windows Server 2008 Failover Clustering.
John Savill
MVP – Clustering and HA
Principal Architect, EMC Consulting
John Savill's Virtualization and High Availability Blog
http://johnsavill.spaces.live.com/
Check out this new blog by Cluster MVP John Savill which will focus on Windows Server Failover Clustering and Hyper-V virtual machines.
Some recent posts include:
· Great Microsoft Virtualization Resources
· Making your Virtual Environment Highly Available the right way
I gave a live webinar yesterday for Windows IT Pro on how to make your Hyper-V based virtual environment highly available the right way which can be seen on http://www.ittv.net and on my video archive at http://www.savilltech.com/videos.html.
I wanted to go over some of the key points of that presentation here and primarily the different types of high availability available to us with Failover Clustering and Hyper-V.
John Savill
MVP – Clustering and HA
Principal Architect, EMC Consulting
PrintBRM.exe, 0×80070043 and Print Clusters - A Workaround
http://www.nullsession.com/2009/01/04/printbrmexe-and-print-clusters-a-workaround/
Since I’ve been working almost 24/7 over the holidays while migrating one huge environment (15.000 users) into a new one in a hurry. That is, without any previous knowledge of the old environment and a very tight schedule, I’ve been using all the shortcuts I can come up with. I quickly realized that PrintBRM would save my butt when it came to migrating printers. I still ended up adding them more or less manually since I migrated from Windows Server 2003 x86 to a Windows Server 2008 x64-based cluster and the time finding the right drivers for it to work flawlessly would’ve been longer than the manual add.
Joachim Nässlander
Microsoft MVP - File Systems & Storage
Senior Specialist, QBranch
Steps to move a DHCP database from a Windows Server 2003 or 2008 to another Windows Server 2008 machine
http://blogs.technet.com/networking/archive/2008/06/27/steps-to-move-a-dhcp-database-from-a-windows-server-2003-or-2008-to-another-windows-server-2008-machine.aspx
The DHCP database schema is different in Windows Server 2008 than it was in Windows Server 2003. This means a few extra steps are necessary when upgrading your cluster and migrating the data on your storage device. The Failover Clustering Migrate a Cluster Wizard will migrate the settings of your clustered DHCP resource groups, then you can apply these steps when migrating the data on your shared storage.
Wayne Melvin
PowerShell for Network Load Balancing (NLB) in Windows Server 2008 R2
Hi Cluster Fans,
In Windows Server 2008 R2 (“R2”) we are introducing PowerShell as the new scripting language for clustering technologies. PowerShell with Network Load Balancing (NLB) will replace NLB.exe and WLBS.exe. The Windows Server 2008 R2 release is the last release for NLB.exe and WLBS.exe. This means it will still be available for use so it doesn’t break legacy scripts, but no improvements have been made so NLB.exe and WLBS.exe will be completely removed in the next release of Windows Server. Do not worry – you will love PowerShell with its numerous benefits over standard command line interfaces, including easily customizable scripts and the dynamic use of variables.
In Windows Server 2008 R2, PowerShell can also be run on Server Core machines. Using PowerShell on a Core NLB cluster, you can directly create and manage your NLB cluster, without needing to manage the Core node through a UI-based remote machine.
This blog post will provide an overview of PowerShell with Network Load Balancing. Also try out PowerShell for Failover Clustering.
How do I get R2 Beta?
The Windows Server 2008 R2 Beta build will be available shortly for deployment and testing. There are numerous ways to get the Windows Server 2008 R2 Beta build which includes Network Load Balancing. If you work for an organization which partners with Microsoft, try contacting your Technology Account Manager (TAM) to see if they can provide you with access. If your organization is enrolled in the Technology Adoption Program (TAP) you may also have access through this channel. Others may enroll in the Microsoft Connect program (http://connect.microsoft.com/) to receive access to major builds.
We want your feedback!
PowerShell is going to be the cluster scripting language for the future – and you have the opportunity to influence its design and use for the next decade during the Beta feedback period. Some high-level areas of feedback for the PowerShell commands (cmdlets) which we are looking for include the following:
· Was it easy to find the cmdlet you wanted?
· Are the parameters consistent between cmdlets?
· Is the in-box help and example useful?
· Has the PowerShell utility met your scripting needs?
· Was there a cmdlet which did something different than you expected from its name or description?
· Anything else?
We encourage you to provide feedback through the appropriate channels on the Microsoft Connect site, through your TAM, or TAP Program Manager. You may also email your feedback to us via the Email link in the upper left corner of this page.
Running Network Load Balancing with PowerShell
The name of the NLB module is NetworkLoadBalancingClusters.
This section provides instructions for running NLB with PowerShell.
· Loading PowerShell with NLB can be done in two ways:
1. Open Network Load Balancing PowerShell Management from the shortcut in Administrative Tools
2. Open PowerShell on your machine through right-clicking and selecting Run as administrator
§ Load the module with the command: Import-Module NetworkLoadBalancingClusters
Network Load Balancing PowerShell Cmdlets
Cmdlets (“command-lets”) form the basis of the PowerShell instruction set. The design goal was for feature parity between the Network Load Balancing Manager GUI and PowerShell, so any operation can be performed on both. This includes the ability to create NLB clusters, manage nodes, manage VIP/DIP addresses, and manage port rules – things which were not achievable from the traditional CLI tools, nlb.exe/wlbs.exe. Additionally, through the cmdlet Get-NlbClusterDriverInfo, you get a lot of insights into the NLB driver.
To get a complete list of the cmdlets, run the following command: Get-Command -Module NetworkLoadBalancingClusters
The following is a list of NLB cmdlets for the Beta release. Note that these are subject to change.
Name
---
Add-NlbClusterNode
Add-NlbClusterNodeDip
Add-NlbClusterPortRule
Add-NlbClusterVip
Disable-NlbClusterPortRule
Enable-NlbClusterPortRule
Get-NlbCluster
Get-NlbClusterDriverInfo
Get-NlbClusterNode
Get-NlbClusterNodeDip
Get-NlbClusterNodeNetworkInterface
Get-NlbClusterPortRule
Get-NlbClusterVip
New-NlbCluster
New-NlbClusterIpv6Address
Remove-NlbCluster
Remove-NlbClusterNode
Remove-NlbClusterNodeDip
Remove-NlbClusterPortRule
Remove-NlbClusterVip
Resume-NlbCluster
Resume-NlbClusterNode
Set-NlbCluster
Set-NlbClusterNode
Set-NlbClusterNodeDip
Set-NlbClusterPortRule
Set-NlbClusterPortRuleNodeHandlingPriority
Set-NlbClusterPortRuleNodeWeight
Set-NlbClusterVip
Start-NlbCluster
Start-NlbClusterNode
Stop-NlbCluster
Stop-NlbClusterNode
Suspend-NlbCluster
Suspend-NlbClusterNode
Help Documentation
PowerShell for NLB certainly has a lot of functionality, but to improve usability, extensive help and examples are built right into the utility. Please refer to this in-box help when you use PowerShell. This is also an area where we would like your feedback – please let us know if there is anything which you cannot find or you believe was misleading.
To get full help for a cmdlet: Get-Help <cmdlet_name> -Full
Let’s take a look at the Add-NlbClusterNode cmdlet:
PS C:/Windows/System32> Get-Help Add-NlbClusterNode –Full
NAME
Add-NlbClusterNode
SYNOPSIS
Adds a new node to the NLB cluster.
SYNTAX
Add-NlbClusterNode [-Force] [-HostName <string>] -InterfaceName <string> [-NewNodeName] <string> [-NewNodeInterface] <string> [<CommonParameters>]
Add-NlbClusterNode [-Force] -InputObject <Cluster[]> [-NewNodeName] <string
> [-NewNodeInterface] <string> [<CommonParameters>]
DETAILED DESCRIPTION
The Add-NlbClusterNode cmdlet adds a new host to the NLB cluster. Once the new host settings are circulated through all cluster hosts, the new cluster host will be in a running state in the cluster.
This operation changes the configuration on all cluster nodes. As a result, the NLB cluster will have to restart the convergence process on all nodes to guarantee that configuration changes have been applied on all nodes and that a consistent state is reached. Any additional operations on the NLB cluster should not be initiated until all cluster nodes have completed the convergence process and are back to the converged state. To check the state of all cluster nodes, use the Get-NlbClusterNode cmdlet. If a configuration change results in the cluster nodes remaining in perpetual convergence, refer to the event log to resolve the configuration inconsistency between the cluster nodes.
PARAMETERS
-Force [<SwitchParameter>]
Performs the operation without prompting for confirmation. By default this operation will ask for confirmation from the user before proceeding.
Required? false
Position? named
Default value
Accept pipeline input? false
Accept wildcard characters? false
-HostName <string>
Specifies the name of the host which is part of the cluster to run this cmdlet against. If this parameter is omitted or if "-HostName ." is used the local cluster is assumed. [Alias: hn]
Required? false
Position? named
Default value
Accept pipeline input? false
Accept wildcard characters? false
-InputObject <Cluster[]>
Specifies the cluster to add the node to.
Required? true
Position? named
Default value
Accept pipeline input? true (ByPropertyName)
Accept wildcard characters? false
-InterfaceName <string>
Specifies the interface where NLB is bound. This is the interface which is part of the cluster to run this cmdlet against.
Required? true
Position? named
Default value
Accept pipeline input? false
Accept wildcard characters? false
-NewNodeInterface <string>
Specifies the interface name on the new cluster node. [Alias: ni]
Required? true
Position? 2
Default value
Accept pipeline input? false
Accept wildcard characters? false
-NewNodeName <string>
Specifies the name of the new cluster node. [Alias: nn]
Required? true
Position? 1
Default value
Accept pipeline input? false
Accept wildcard characters? false
<CommonParameters>
This cmdlet supports the common parameters: -Verbose, -Debug,
-ErrorAction, -ErrorVariable, -WarningAction, -WarningVariable, -OutBuffer and -OutVariable. For more information, type, "get-help about_commonparameters".
INPUT TYPE
Microsoft.NetworkLoadBalancingClusters.PowerShell.Cluster
RETURN TYPE
Microsoft.NetworkLoadBalancingClusters.PowerShell.Node
NOTES
-------------------------- EXAMPLE 1 --------------------------
C:/PS>Get-NlbCluster node1 | Add-NlbClusterNode -NewNodeName node2 -NewNode
Interface vlan-3
Name State Interface HostID
---- ----- --------- ------
node2 Converged vlan-3 2
Description
-----------
This command adds host node2 to the cluster on node1.
RELATED LINKS
Get-NlbClusterNode
Remove-NlbClusterNode
Resume-NlbClusterNode
Set-NlbClusterNode
Stop-NlbClusterNode
Suspend-NlbClusterNode
To get full help for all NLB cmdlets: Get-Command -Module NetworkLoadBalancingClusters | %{ Get-Help $_.Name -Full }
Example
Here’s a sample PowerShell script where I create an NLB cluster, add nodes to the cluster, manage the port rules, and get some information about the cluster and port rules.
# Create the NLB cluster on the local machine
New-NlbCluster -InterfaceName vlan-4 -ClusterName ahmedb
nlbclus1 -ClusterPrimaryIP 4.0.9.99 -SubnetMask 255.0.0.0
# Add a node to the cluster
Get-NlbCluster | Add-NlbClusterNode -NewNodeName node2 -NewNodeInterface vlan-4
# Get some information about the NLB cluster
Get-NlbCluster
Get-NlbClusterNode
Get-NlbClusterVip
Get-NlbClusterNodeDip
Get-NlbClusterPortRule
# Get rid of the default port rule
Get-NlbClusterPortRule | Remove-NlbClusterPortRule
# Add specific port rules
Get-NlbCluster | Add-NlbClusterPortRule -StartPort 80 -EndPort 80 -Affinity None
Get-NlbCluster | Add-NlbClusterPortRule -StartPort 443 -EndPort 443
Good luck with your PowerShell and NLB deployments and please send us your feedback!
Thanks,
Symon Perriman, Program Manager
Ahmed Bisht, Senior Program Manager
Clustering & High Availability
PowerShell for Failover Clustering in Windows Server 2008 R2
Hi Cluster Fans,
In Windows Server 2008 R2 (“R2”) we are introducing PowerShell as the new scripting language for clustering technologies. PowerShell with Failover Clustering will replace Cluster.exe and the Windows Server 2008 R2 release will be the deprecation release for Cluster.exe. This means it will still be available for use so it doesn’t break legacy scripts, but no improvements have been made and Cluster.exe will be completely removed in the next release of Windows Server. This allows ample time for you to learn (and love) PowerShell.
PowerShell provides numerous benefits over standard command line interfaces, including easily customizable scripts and the dynamic use of variables. In Windows Server 2008 R2, PowerShell can also be run on Server Core machines. Using PowerShell on a Core cluster, you can directly run cluster Validation and generate dependency reports, without needing to manage the Core node through a UI-based remote machine.
This blog post will provide an overview of PowerShell with Failover Clustering. In the next few weeks, a post about PowerShell with Network Load Balancing (NLB) will be added to the site.
How do I get R2 Beta?
There are numerous ways to get the Windows Server 2008 R2 Beta build which includes Failover Clustering (on Enterprise and Datacenter editions). If you work for an organization which partners with Microsoft, try contacting your Technology Account Manager (TAM) to see if they can provide you with access. If your organization is enrolled in the Technology Adoption Program (TAP) you may also have access through this channel. Others may enroll in the Microsoft Connect program (http://connect.microsoft.com/) to receive access to major builds. The Beta build will be available very shortly for deployment and testing.
We want your feedback!
PowerShell is going to be the cluster scripting language for the future – and you have the opportunity to influence its design and use for the next decade during the Beta feedback period. Some high-level areas of feedback for the PowerShell commands (cmdlets) which we are looking for include the following:
· Was it easy to find the cmdlet you wanted?
· Are the parameters consistent between cmdlets?
· Is the in-box help and example useful?
· Has the PowerShell utility met your scripting needs?
· Was there a cmdlet which did something different than you expected from its name or description?
· Anything else?
We encourage you to provide feedback through the appropriate channels on the Microsoft Connect site, through your TAM, or TAP Program Manager. You may also email your feedback to us via the “Email” link in the upper left corner of this page.
Running Failover Clustering with PowerShell
The name of the Failover Clustering module is FailoverClusters.
Loading PowerShell with Failover Clustering can be done in two ways:
1. Open Failover Cluster PowerShell Management from the shortcut in Administrative Tools
§ This option will appear after the Failover Clustering feature is installed
2. Open PowerShell on your machine through right-clicking and selecting Run as administrator
§ Load the module with the command: Import-Module FailoverClusters
Failover Clustering PowerShell Cmdlets
Cmdlets (“command-lets”) form the basis of the PowerShell instruction set. The design goal was for feature parity between the Failover Cluster Manager GUI and PowerShell, so any operation can be performed on both (with cluster migration being the exception, unavailable with PowerShell). Other new R2 Failover Clustering features are also supported by PowerShell, including Cluster Shared Volumes (CSV) and Live Migration. Integration with and manageability of Hyper-V Virtual Machines (VMs) is also important and PowerShell give you the ability to create and manage highly-available VMs, configure CSV volumes, and perform a Quick Migration (Move-ClusterGroup) or a Live Migration (Move-ClusterVirtualMachineRole).
To get a complete list of the cmdlets, run the following command: Get-Command -Module FailoverClusters
The following is a list of Failover Clustering cmdlets for the Beta release. Note that these are subject to change.
Name
----
Add-ClusterDisk
Add-ClusterFileServerRole
Add-ClusterGenericApplicationRole
Add-ClusterGenericScriptRole
Add-ClusterGenericServiceRole
Add-ClusterGroup
Add-ClusterNode
Add-ClusterPrintServerRole
Add-ClusterResource
Add-ClusterResourceDependency
Add-ClusterResourceType
Add-ClusterServerRole
Add-ClusterSharedVolume
Add-ClusterVirtualMachineRole
Block-ClusterAccess
Clear-ClusterDiskReservation
Clear-ClusterNode
Fail-ClusterResource
Get-Cluster
Get-ClusterAccess
Get-ClusterAvailableDisk
Get-ClusterGroup
Get-ClusterLog
Get-ClusterNetwork
Get-ClusterNetworkInterface
Get-ClusterNode
Get-ClusterOwnerNode
Get-ClusterParameter
Get-ClusterQuorum
Get-ClusterResource
Get-ClusterResourceDependency
Get-ClusterResourceDependencyReport
Get-ClusterResourceType
Get-ClusterSharedVolume
Grant-ClusterAccess
Move-ClusterGroup
Move-ClusterResource
Move-ClusterSharedVolume
Move-ClusterVirtualMachineRole
New-Cluster
Remove-Cluster
Remove-ClusterAccess
Remove-ClusterGroup
Remove-ClusterNode
Remove-ClusterResource
Remove-ClusterResourceDependency
Remove-ClusterResourceType
Remove-ClusterSharedVolume
Resume-ClusterNode
Resume-ClusterResource
Set-ClusterLog
Set-ClusterOwnerNode
Set-ClusterParameter
Set-ClusterQuorum
Set-ClusterResourceDependency
Start-Cluster
Start-ClusterGroup
Start-ClusterNode
Start-ClusterResource
Stop-Cluster
Stop-ClusterGroup
Stop-ClusterNode
Stop-ClusterResource
Suspend-ClusterNode
Suspend-ClusterResource
Test-Cluster
Update-ClusterIPResource
Update-ClusterVirtualMachineConfiguration
Help Documentation
This all sounds pretty good, right? But what happens when you cannot figure out what command syntax is needed? Well PowerShell has all the help documentation built into the PowerShell utility itself and even includes examples. Please refer to this in-box help when you use PowerShell. This is also an area where we would like your feedback – please let us know if there is anything which you cannot find or you believe was misleading.
To get full help for a cmdlet: Get-Help <cmdlet_name> -Full
Let’s take a look at the Add-ClusterDisk cmdlet:
PS C:/Users/symonp> Get-Help Add-ClusterDisk -Full
NAME
Add-ClusterDisk
SYNOPSIS
Make a new disk available for use in a failover cluster. The disk (LUN) must be exposed to all nodes in the failover cluster, and should not be exposed to any other servers.
SYNTAX
Add-ClusterDisk [-InputObject] <ClusterDiskInfo[]> [-confirm] [-whatif] [<CommonParameters>]
DETAILED DESCRIPTION
When adding a disk, make sure that the configuration of the storage allows the operating system to recognize and mount the disk as needed. The disk must be a basic disk (not a dynamic disk) and should not be exposed to servers outside the cluster. The cmdlet Get-ClusterAvailableDisk gets information about disks that you can add to the cluster.
PARAMETERS
-InputObject <ClusterDiskInfo[]>
Required? true
Position? 1
Default value
Accept pipeline input? true (ByValue)
Accept wildcard characters? false
-Confirm [<SwitchParameter>]
Prompts you for confirmation before executing the command.
Required? false
Position? named
Default value
Accept pipeline input? false
Accept wildcard characters? false
-WhatIf [<SwitchParameter>]
Describes what would happen if you executed the command without actually executing the command.
Required? false
Position? named
Default value
Accept pipeline input? false
Accept wildcard characters? false
<CommonParameters>
This cmdlet supports the common parameters: -Verbose, -Debug,
-ErrorAction, -ErrorVariable, -WarningAction, -WarningVariable,
-OutBuffer and -OutVariable. For more information, type,
"get-help about_commonparameters".
INPUT TYPE
Microsoft.FailoverClusters.PowerShell.ClusterDiskInfo
RETURN TYPE
Microsoft.FailoverClusters.PowerShell.ClusterResource
NOTES
-------------------------- EXAMPLE 1 --------------------------
C:/PS>Get-ClusterAvailableDisk | Add-ClusterDisk
Name State Group ResourceType
---- ----- ----- ------------
Cluster Disk 7 OnlinePending Available Storage Physical Disk
Cluster Disk 8 OnlinePending Available Storage Physical Disk
Description
-----------
This command adds to the cluster all disks that are ready for cluster use but have not been added to the cluster yet.
-------------------------- EXAMPLE 2 --------------------------
C:/PS>Get-ClusterAvailableDisk | ?{ $_.ScsiAddress -eq 50331651 } | Add-ClusterDisk
Name State Group ResourceType
---- ----- ----- ------------
Cluster Disk 4 OnlinePending Available Storage Physical Disk
Description
-----------
This command adds to the cluster a disk (with the given SCSI Address) that is ready for cluster use but has not been added to the cluster yet.
RELATED LINKS
Test-Cluster
Get-ClusterAvailableDisk
To get full help for all Failover Clustering cmdlets: Get-Command -Module FailoverClusters | %{ Get-Help $_.Name -Full }
Example
Here’s a sample PowerShell script where I set some variables, create a highly-available File Server, get some information about the cluster and resources, move the File Server, then delete it.
# Set some variables
$Node1 = "symonp-n1" ; $Node2 = "symonp-n2"
$FileServerGroupName = "symonp-fsBlog"
$FileServerDiskResourceName = "Cluster Disk 1"
# Create a highly available file server
Add-ClusterFileServerRole -Storage $FileServerDiskResourceName –Name $FileServerGroupName
# See which resources are in my group
Get-ClusterGroup $FileServerGroupName | Get-ClusterResource
# Get resources on a specific node
Get-ClusterNode $Node1 | Get-ClusterResource
Get-ClusterNode $Node2 | Get-ClusterResource
# Move file server cluster group to this node if it is on another node
Move-ClusterGroup -Group $FileServerGroupName -NodeName $env:computername
# Delete the highly available file server
Remove-ClusterGroup $FileServerGroupName -RemoveResources
Good luck with your PowerShell deployments and please send us your feedback!
Thanks,
Symon Perriman
Program Manager
Clustering & HA
Clustering and HA Resources
Hi Cluster Fans,
Resources can be hard to find, so every few months we will be publishing an updated list of useful documents, guides and information to this blog (http://blogs.msdn.com/clustering/). If there is any important Microsoft content which you feel is missing, let us know by clicking the 'email' link in the upper left corner of the page and send us the resource and URL.
Thanks,
Symon Perriman
Program Manager
Clustering & HA
General Resources
· Cluster Team Site: Clustering Technical Resources
· Guide: Failover Clustering Deployment
· Guide: Validating Hardware for a Failover Cluster
· Guide: Migrating Cluster Settings
· Guide: Configuring the Quorum in a Failover Cluster
· Guide: Configuring Accounts in Active Directory
· Guide: Configure a Service or Application for High Availability
· Guide: Modifying Settings for a Failover Cluster
· Guide: Installing a Failover Cluster
· Guide: Creating a Failover Cluster
· Guide: Cluster Requirements
· Guide: Validating a cluster
· Guide: Managing a Failover Cluster
· Guide: The Failover Cluster Management Snap-In
· TechNet: Support Policy
· Webcast: Top 10 Windows Server 2008 Failover Clustering Enhancements over Windows Server 2003 Clustering, Based on Best Practices (Level 300)
· Webcast: Failover Clustering 101
· Webcast: Achieving High Availability with Windows Server “Longhorn” Clustering (Level 200)
- Webcast: Microsoft Webcast: Reducing IT Overhead with Windows Server 2008 Storage Features
- Webcast: TechNet Webcast: Build High-Availability Infrastructures with Windows Server 2008 Failover Clustering
- Webcast: IT Manager Webcast: Delivering High Availability to Your Infrastructure
- Webcast: TechNet Webcast: Failover Cluster Validation and Troubleshooting with Windows Server 2008
- Webcast: TechNet Webcast: Failover Clustering and Quorum in Windows Server 2008 Enterprise Storage
- Webcast: TechNet Virtual Lab: Windows Server 2008 Enterprise Failover Clustering Lab
· Whitepaper: Failover Cluster Architecture Overview
· Whitepaper: Microsoft’s HA Strategy
· Whitepaper: Overview of Failover Clustering
Core
· Utility: Remote Server Administration Tools (simplifies Server Core configurations)
· Guide: Server Core
· TechNet: Installation
· Webcast: How Microsoft does IT: Enhancing High Availability with Server Core in Windows Server 2008
Exchange Server
- Lab: TechNet Virtual Lab: Exchange Server 2007 Standby Continuous Replication
- Lab: TechNet Virtual Lab: Using Cluster Continuous Replication (CCR) in Exchange 2007
- TechNet: Installing Cluster Continuous Replication (CCR) on 2008
- TechNet: Deploying Exchange 2003 in a Cluster
- TechNet: Planning for Cluster Continuous Replication (CCR)
- TechNet: Installing CCR on Windows Server 2008
- Webcast: How Microsoft IT Implemented New Storage Designs for Exchange Server 2007
File Server
· Guide: Configuring a Two-Node File Server Failover Cluster
· TechNet: Creating a Clustered File Server checklist
· TechNet: Create a Shared Folder in a Clustered File Server
· WebCast: TechNet Webcast: Prepare Yourself for Windows Server 2008 (Part 5 of 8): New File Server Features
· WebCast: How Microsoft IT Deploys Windows 2008 Clusters for File Services
· Webcast: New File Server Features of Windows Server 2008 (Level 200)
Hyper-V
· Guide: Testing Hyper-V and Failover Clustering
· Guide: Getting Started with Hyper-V
· Guide: Design for a Failover Cluster in Which All Nodes Run Hyper-V
· TechNet: High-Availability for a Server Running Hyper-V
· TechNet: Requirements and Recommendations for Failover Clusters in Which All Nodes Run Hyper-V
· TechNet: Failover Cluster in which the Servers run Hyper-V
· Webcast: TechNet Webcast: High Availability with Hyper-V
· Webcast: TechNet Webcast: 24 Hours of Windows Server 2008 (Part 24 of 24): High Availability with Hyper-V
· Webcast: TechNet Webcast: Creating Business Continuity Solutions Using Windows Virtualization
· Whitepaper: Quick Migration with Hyper-V
Multi-Site Clustering
· Cluster Team Site: http://www.microsoft.com/windowsserver2008/en/us/clustering-multisite.aspx
· Guide: Deployment Considerations for Windows Server 2008 failover cluster nodes on different, routed subnets
· Webcast: TechNet Webcast: Geographically Dispersed Failover Clustering in Windows Server 2008 Enterprise
· Webcast: How You Can Achieve Greater Availability with Failover Clustering Across Multiple Sites (Level 300)
· Whitepaper: Multi-site Clustering
Network Load Balancing
· Guide: NLB Troubleshooting Overview
· Guide: Server Core: Install the NLB feature
· Guide: Create/manage/destroy NLB clusters via NLB Manager remotely from another server, or from RSAT client (admin pack) on Vista
· TechNet: Configuring NLB with Terminal Services
· TechNet: NLB Deployment Guide
· TechNet: Implementing a new NLB Cluster
· TechNet: Verifying the NLB Cluster and Enabling Client Access
· TechNet: Overview of NLB
· TechNet: Creating NLB Clusters
· TechNet: Managing NLB Clusters
· TechNet: Setting NLB Parameters
· TechNet: Controlling Hosts on NLB clusters
· TechNet: Troubleshooting for System Event Messages Related to NLB Cluster
· TechNet: User Interface: NLB Manager
· TechNet: Upgrading a NLB Cluster
· Webcast: 24 Hours of Windows Server 2008 (Part 23 of 24): Failover Clustering and Network Load Balancing
SQL Server
- Guide: SQL Server 2000 with Failover Clustering
- MSDN: Getting Started with SQL Server 2008 Failover Clustering
- MSDN: Configuring SQL Server 2005 Failover Clustering
- MSDN: Configuring SQL Server 2000 Failover Clustering
- TechNet: Database Mirroring and Failover Clustering
- TechNet: SQL Server 2005 Database Mirroring FAQs
- TechNet: Database Mirroring in SQL Server 2005
- Webcast: Microsoft SQL Server 2005 Failover Clustering on Windows Server 2008
- Webcast: TechNet Webcast: 24 Hours of SQL Server 2008: Ensuring Business Continuity
- Webcast: TechNet Webcast: Overview of SQL Server Availability Features and Upcoming Improvements
- Webcast: TechNet Webcast: Achieving Higher Scalability with SQL Server on Windows Server 2003 R2 Enterprise Edition (Level 300)
- Webcast: Ensuring Business Continuance with SQL Server 2005 Data Availability Solutions (Level 300)
- Webcast: Clustering Windows Server 2003 and SQL Server 2000/2005 (Level 200)
- Webcast: SQL Server 2005 for the IT Professional (Part 7 of 11): Technologies and Features to Improve Availability (Level 200)
- Webcast: SQL Server 2005 Failover Clustering for SQL Server 2000 Users (Level 200)
- Webcast: An Introduction to How SQL Server 2005 Can Help You Deliver Highly Available Database Systems (Level 200)
- Webcast: Clustering Windows Server 2003 and SQL Server 2000 and 2005 (Level 200)
- Webcast: How to cluster Microsoft SQL Server 2005 by using Microsoft Virtual Server
- Whitepaper: SQL Server 2008 Replication: Providing High Availability using Database Mirroring
Clustering in Windows Server 2008 R2
Hi Cluster Fans,
It has been a while since our last post and that is because we have been so busy unleashing Clustering in Windows Server 2008 R2 (“R2”) to the world. At several recent conferences, including TechEd EMEA and WinHec, we publically announced our R2 plans and features for Failover Clustering and Network Load Balancing. Over the next few months we will be discussing each of these new features on this blog, so check back regularly to learn all about clustering in R2.
New Failover Clustering features in R2:
· Cluster Shared Volumes (CSV) – A distributed access file system optimized for Hyper-V allowing virtual machines and their disk resources to reside be on any cluster node
· Live Migration – Move virtual machines between different physical machines while keeping them running and maintaining client connections
· PowerShell Support – The scripting language of the future which will gradually replace cluster.exe
· DFS-Replication support – Configure members servers in your replication group to be highly available for uniterrupted and failure resilient replication services
· Remote Desktop / Terminal Services support – Make the Connection Broker highly available ensuring that clients are reconnected to their same session or virtual machine within a server farm
· Network Prioritization – Plan your internal cluster network for efficiency, giving the fastest network the highest priority for internal traffic (heartbeat, CSV & Live Migration traffic)
· Read-Only APIs – This security enhancement allows admins to query the state of the cluster, but not perform any actions, making it ideal for first-level triage who "can look, but not touch"
· ETW logging channels – New Crimson channel makes cluster-wide events easier to manage
· Performance Monitor – Clustering counters allow the user to monitor the cluster and tweak it for optimal performance
· Enhanced Validation – Improvements to the functional test tool with additional tests which execute on production cluster nodes to ensure they are running optimally, with best practices deployed
· Migration – The clustering upgrade path now supports more workloads and configurations and offers detailed information about what will be migrated and any additional steps required by the user
New Network Load Balancing features in R2:
· Extended Affinity – Ensures clients are reconnected to the same node to retain cached information if they are disconnected
· PowerShell Support – The new NLB scripting language which will gradually replace nlb.exe and wlbs.exe
We’ve also made additional improvements to virtually every workload, adding greater resiliency, functionality, and parity with standalone servers.
Thanks,
Symon Perriman
Program Manager
Clustering & HA
What is the purpose of the “Repair Active Directory Object” option?
Something changed the CNO’s password without the CNO knowing.
One of the responsibilities of Network Name resources is to rotate the passwords of the machine accounts. While it is online, each network name changes its password according to domain and local machine policy. Because the CNO has full permissions over all the VCOs in the cluster, VCO Network Names will repair themselves, under the guise of the CNO, if the password gets out of sync.
But, if the CNO password is different from what is stored in the cluster database, no Network Names in the cluster will be able to come online. The Repair Active Directory Object option fixes this password. This can be accessed through the UI by right-clicking on the offline Network Name, selecting More Actions…, then clicking Repair Active Directory Object.
Since this operation modifies an Active Directory Object, you will need the correct permissions. This should be run in the Cluster Administrator snap-in from an account that has Special Permissions over the CNO in Active Directory. This is usually the account that created the cluster. If you cannot find anyone who has these permissions, you will need to find a Domain Administrator.
Thanks,
Matt Kurjanowicz
Software Development Engineer
Clustering & High Availabilty
Clustering is coming to TechEd EMEA!
Next week the Clustering and High Availability team will be traveling to Barcelona, Spain for one of Europe’s largest IT conferences, TechEd EMEA ITPro, from November 3-7. Throughout this week we will be giving presentations, demos, chalk-talks, and instructor led labs, in addition to being available for individual questions at the clustering booth on the events floor whenever it is open. We will also be announcing our new features for Windows Server 2008 R2. For more information about TechEd EMEA, visit: http://www.microsoft.com/emea/teched2008/itpro/.
Here are the Clustering and High-Availability events:
Breakout Sessions
SVR 311 & 312 – Failover Clustering with WS08 R2
• Presenter(s): Symon Perriman, Microsoft
• Abstract: Come and learn about all the new enhancements that are going to be delivered in Failover Clustering with Windows Server 2008 R2. This session will drill into updates to the cluster validation tool, the new cluster configuration program and other exciting features. We will be focusing on different features in each presentation.
SVR 304 – WS08 Failover Clustering Troubleshooting Tips and Best Practices
• Presenter(s): David Dion, Microsoft
• Abstract: As Windows Server operating systems become increasingly accepted in the large scale and high-end mission-critical parts of organizations, the requirements for disaster tolerance and business continuance become more and more important. The goal of this session is to cover the considerations on how you can build a complete High Availability solution with Windows Server 2008 Enterprise Failover Clustering to ensure that there is no single point of failure.
SVR 305 – Configuring Hyper-V for High Availability
• Presenter(s): Ralf Schnell, Microsoft
• Abstract: Running virtualized operating systems introduces a dependency on the underlying virtualization infrastructure. If the virtualization host is a standalone machine, it actually becomes a single point of failure for all guest systems running on top of it. So, let's get this thing clustered! But how do we do that and do so in a way that allows every single guest system to move around in that cluster independently from all the others? Well, turning one single virtual machine stored on a shared LUN into a Cluster resource has become almost embarrassingly simple with Hyper-V. But that's one - how about one hundred or one thousand? We might want to avoid using drive letters in that case - unless you want to limit yourself to 22 virtual machines on a 16 node cluster. How then do we store the guest systems data and configuration files? Actually there are multiple ways of how to accomplish this, and we'll look into the technical details, and the advantages and disadvantages of those, and try them out live on stage.
SVR 306 – WS08 R2 Hyper-V Architecture, Scenarios & Networking
• Presenter(s): Jeff Woolsey, Microsoft
• Abstract: This session provides a high-level overview of the architecture of Hyper-V and VMM. The session then introduces the audience to an all-up view of the different scenarios enabled by server virtualization and virtualization management. Product demonstrations within this presentation highlight the features of Hyper-V and Microsoft System Center Virtual Machine Manager 2008 in the context of the following four key use scenarios: 1) Consolidating production servers; 2) Providing business continuity and high availability; 3) Creating an agile testing and development environment; 4) Enabling the dynamic datacenter.
SVR 202 – WS08 R2 Hyper-V Feature Dive
• Presenter(s): Rajesh Davé & Jeff Woolsey, Microsoft
• Abstract: Want to get a sneak peek at what's new in Hyper-V for Windows Server 2008 R2? This session focuses on the new capabilities of Windows Server 2008 R2 Hyper-V. The session also covers the base architecture of Hyper-V and provides guidance on key areas like storage management, performance and more.
DAT 302 – Making Sense of the High Availability Tools in SQL Server 2008
• Presenter(s): Andrew Fryer, Microsoft
• Abstract: SQL Server can be designed to be 'always on' but what do you have to do to achieve this; do you need to make key design decisions and what are the implications of making them. 'Always On' can be achieved with apparently conflicting technologies, this session looks at all of these including clustering, mirroring, replication to see how they differ but more importantly how they can work together to form a complete strategy to ensure you can always retrieve your data.
UNC 306 – High Availability in Exchange 2007 SP1, Part 1: CCR/SCC Failover Clusters
• Presenter(s): Scott Schnoll, Microsoft
• Abstract: Are you digging out your backups every time there is a failure? Are you paying a lot for that hardware replication that promises zero data loss? Join us in this session to learn about how you can provide highly available e-mail with a reduced TCO using Exchange Server 2007 SP1 HA features and why you should use CCR.
Interactive Sessions
SVR 05-IS – Failover Clustering Design
• Presenter(s): Symon Perriman & David Dion, Microsoft
• Abstract: Does the word cluster leave a sour taste in your mouth? Does it strike fear into your heart? Come and learn about how simple Windows Server 2008 Failover Clustering is and how you can now be successful. Come and share the pain you have with clustering today or reasons you don't deploy them even when you have a need to implement a high availability solution. Come to this session and learn about how you can use the enhancements; be ready to ask tough questions and get answers.
SVR 11-IS – Windows Server 2008 R2 - Why should I care?
• Presenter(s): Iain McDonald, David Dion, Dan Reger & Others, Microsoft
• Abstract: What is Windows Server 2008 R2? Why should I care about it when Windows Server 2008 has only been release for a short time? What is a R2 release anyway? Come and participate in an open discussion with a group of R2 experts representing virtualization, management, clustering, web platform and more.
Labs & Demos
SVR 02-ILL (Repeated) – Windows Server 2008 High Availability and Failover Clustering
• Presenter(s): Symon Perriman, Microsoft
• Abstract: This lab offers an overview of the failover clustering capabilities of Windows Server 2008, including the tools for simplified setup, validation and management.
SVR 03-PD (Repeated) – Building a Failover Cluster with WS08 Core
• Presenter(s): Joachim Nässlander, MVP - File Systems & Storage, Qbranch
• Abstract: This session will show you how to configure and build a cluster with Windows Server 2008 Core. It includes firewall configuration, iSCSI connections, remote management and other technical solutions. The finished cluster can be used to deliver almost any clusterable resource with a higher level of reliability and less management thanks to the architecture of Windows Server 2008 Core.
SVR 53-HOL – WS08: High Availability
• Hands On Lab
• Abstract: This lab will introduce you to the components that provide Windows Server 2008 High Availability. You will begin by configuring an ISCSI SAN using the Microsoft ISCSI Software Target and ISCSI Initiator on Windows Server 2008 Core. Once the SAN is operational, you will create two highly available resources; a file server, and a DCHP server. Once you have verified that the file server correctly responds to a failed node, you will perform some basic administration tasks using the new Cluster.exe command.
SVR 69-HOL – High Availability with WS08 Network Load Balancing
• Hands On Lab
• Abstract: With this lab discover how Network Load Balancing with Microsoft Windows Server 2008 Enterprise enables you to easily build a highly available infrastructure IIS7 Infrastructure.
SVR 54-HOL – WS08 Hyper-V: Exploring Hyper-V and Implementing Quick Migration
• Hands On Lab
• Abstract: This lab is intended for IT Professionals who are deploying virtual machines using Windows Server 2008 Hyper-V, and wish to make those virtual machines highly available. You will begin by exploring and configuring a new failover cluster. You will then create new virtual machines, and store those virtual machines on a SAN, for use with the cluster. Finally you will configure the virtual machines as highly available and configure them to fail between cluster nodes. When completed, you will be able to perform quick migration on those virtual machines.
UNC13-HOL Using Microsoft Exchange Server 2007 Cluster Continuous Replication
• Hands On Lab
• Abstract: In this lab, learn how to use Exchange Server 2007 Cluster Continuous Replication. Gain hands-on experience by configuring Windows Server 2003 Cluster Services Exercise, installing and configuring Active and Passive Exchange Server 2007, and moving Exchange Server 2007 resources between cluster nodes.
We look forward to seeing you there!
Symon Perriman
Program Manager
Clustering & HA
Preferred Owners in a Cluster
A recent email conversation I had prompted me to write this entry about Preferred Owners. The Preferred Owners setting for a resource group is one of those things which has an inherent counter-intuitiveness to it.
The feature is described very well in KB 299631 (http://support.microsoft.com/kb/299631), so I won’t give a thorough explanation. The key point I want to make is that, when you set the preferred owners for a group to a subset of the nodes in a cluster, you’re not saying “I want the group to failover only to these nodes”. What you’re effectively saying is, “please reorder the nodes such that these are at the front of the list.” The rest of the cluster nodes will be appended to the list, and the group will still failover to every node in the cluster before going back to the first node in the preferred owners list.
In other words, in a 4 node cluster, when an administrator sets the preferred owners for a group to {3, 4}, I have a feeling that they are thinking that, if the group is on node 3, it will failover to node 4 as long as node 4 is up, and if it’s on node 4, it will similarly failover to node 3 if possible, and only failover to nodes 1 or 2 if node 3 is down.
Just remember that the rest of the nodes are added to the end of the preferred owners list. So internally, the preferred owners list is {3, 4, 1, 2}. If the group is on node 4 and fails, it will move to node 1, not node 3.
Ultimately, it’s about availability. If the group fails on node 3, and then also fails on node 4, it’s probably better to try the other nodes, instead of retrying on node 3.
(The case is different for planned or manual group moves. If you move the group without specifying a specific target node, then it will always move to a node in the preferred owners list.)
The other two means of controlling group movement provide progressively stronger assurances that the group will move only within a subset of nodes:
· Anti-Affinity Keywords: will failover to a node where there is no other group with the same anti-affinity keyword, if possible. If no such node is available, then it will failover to any available node.
o Details: http://msdn.microsoft.com/en-us/library/aa369651(VS.85).aspx
· Possible Owners: will absolutely, positively not come online on a node that is not a possible owner. If no possible owner nodes are up, then the group will still failover to a node that’s not a possible owner, but it will not come online.
o Details: http://msdn.microsoft.com/en-us/library/aa367173(VS.85).aspx
If your are noticing unusual behavior on your Server 2008 cluster, you may want to apply this hotfix: http://support.microsoft.com/kb/950181.
I hope this clears things up.
Thanks,
Jonathan Fischer
Senior Software Development Engineer
Clustering & High Availability
Clustering Videos on the Web
Hi Cluster Fans,
We have some great webcasts to share with you created by one of the team’s Most Valuable Professionals (MVP), John Savill. (What is a MVP? Visit: http://mvp.support.microsoft.com) John has shared some of his clustering work from website, SavillTech.com.
· Creating Windows Server 2008 Failover Clusters: http://www.savilltech.com/Videos/clustercreate/ClusterCreate.wmv
· Configuring a Windows Server 2008 Failover Cluster from the command line: http://www.savilltech.com/Videos/clustercmd/clustercmd.wmv
· Understanding Failover Cluster Quorum: http://www.savilltech.com/Videos/ClusterQuorum/ClusterQuorum.wmv
· Hyper-V Quick Migration: http://www.savilltech.com/Videos/QuickMigration/QuickMigration.wmv
· Configuring iSCSI connections from the command line: http://www.savilltech.com/Videos/iscsicli/iscsicli.wmv
For a complete list of John’s videos, you can visit here: http://www.savilltech.com/videos.html.
The clustering team is always looking for some new MVPs, people passionate in technology and active the high-availability community. For more information, email ClusMVP@microsoft.com.
Thanks,
The Clustering and High-Availability Team
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