RAC 常识

What's the difference between "crsctl start crs" and new parameter on 11.2 "crsctl start cluster" the both have the same result?
We can say that not has the same result.
crsctl start/stop crs - Manage start/stop the entire Oracle Clusterware stack on a node, including the OHASD process, this command is to be used only on the local node..
crsctl start/stop cluster - Manage start/stop the Oracle Clusterware stack on local node if you do not specify either -all or -n and nodes remote if option -n or -all be specified , NOT including the OHASD process. You can't start/stop clusterware stack without OHASD process running.
Despite crsctl start/stop crs manage entire Oracle Clusterware stack on local node crsctl start/stop crs not allow you to manage remote nodes, unlike crsctl start/stop cluster that allows you to manage all the nodes, but if the process OASH is runing.
To manage Oracle Clusterware Stack on remote nodes, the ohasd (Oracle High Availability Services Daemon) must be running on all managed nodes. (i.e using crsctl start cluster -n <node1>, <node2>)
Then if you try use crsctl start cluster -n node1,node2 and your local node is node1 and on node1 or node2 OHASD not running this command will fails. 


大部分RAC配置中,listener.ora内除了监听VIP外,还同时监听了public IP.这里为什么要监听public IP呢?是否是多余的可以去掉呢?
netca by default listens on public ip.
listening on public ips usually provides connectivity to some old client softwares which are using public ips to connect to the database. if you remove public ips, connection from those clients will fail.
if you are sure that no one is using public ips to connect to the db, of course you can remove the public ips in listener. make sure your local_listener in your db is using vips correctly before you do so.

1,查看CRS状态
crsctl check crs
crsctl check has
crsctl check cluster
crsctl check cluster -all
crsctl stat res -t 
crsctl stat res -t -init

2,VOT磁盘查询
crsctl query css votedisk

3,Verify the integrity of OCR:
ocrcheck

4,查看资源状态
crsctl stat res -t
crsctl stat res -t -init

5，启动
crsctl start has
crsctl start cluster  
crsctl start cluster -all
crsctl start cluster -n cqracdb1 

[启动整个集群，包括OHASD在一个节点]

crsctl start crs

6，停止
crsctl stop cluster -n cqracdb1 
crsctl stop cluster [-f]
crsctl stop cluster -all
crsctl stop has

[全部停止包括OHASD]
crsctl stop crs -all -f

7，查看数据库状态
srvctl status database -d cqdb
查看节点资源状态
srvctl status nodeapps
查看数据库的配置
srvctl config database -d cqdb
查看asm的配置
srvctl config asm -a 
查看TNS配置
srvctl config listener -a
查看SCAN
srvctl status scan
停止数据库
srvctl stop instance -d cqdb -i "orcl3,orcl4" -o immediate

查询crs状态：
crsctl config crs
crsctl config has