转 Multi-Master Replication Manager for MySQL MMM安装手册

 [[Installation Guide]] Multi-Master Replication Manager for MySQL

 转： http://mysql-mmm.org/mmm2:guide

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−Table of Contents

• Installation Guide
  • Basic configuration of master 1
  • Create users
  • Synchronisation of data between both databases
  • Setup replication
  • Install MMM
    • Create user
    • Monitoring host
    • Database hosts
    • Configure MMM
  • Start MMM
    • Start the agents
    • Start the monitor

Installation Guide

Note: this guide is a draft, feel free to make changes if you see anything that can be improved, expanded on or correctedThis installation guide describes a installation of MMM 2 (without the MMM tools) based on Debian Lenny (5.0)

A basic installation contains at least 2 database servers and 1 monitoring server. In this guide, I used 5 servers with Debian Lenny (5.0)

functioniphostnameserver idmonitoring host192.168.0.10mon-master 1192.168.0.11db11master 2192.168.0.12db22slave 1192.168.0.13db33slave 2192.168.0.14db44

I used the following virtual IPs. They will be distributed across the hosts byMMM.

iproledescription192.168.0.100writerYour application should connect to this IP for write queries.192.168.0.101readerYour application should connect to one of these four IPs for read queries192.168.0.102reader192.168.0.103reader192.168.0.104reader

Basic configuration of master 1

First we install MySQL on all hosts:

aptitude install mysql-server

Then we edit the configuration file /etc/mysql/my.cnf and add the following lines - be sure to use different server ids for all hosts:

server_id           = 1log_bin             = /var/log/mysql/mysql-bin.log log_bin_index       = /var/log/mysql/mysql-bin.log.index relay_log           = /var/log/mysql/mysql-relay-bin relay_log_index     = /var/log/mysql/mysql-relay-bin.index expire_logs_days    = 10 max_binlog_size     = 100M log_slave_updates   = 1

Then remove the following entry:

bind-address = 127.0.0.1

Set to number of masters:

auto_increment_increment = 2

Set to a unique, incremented number, less than auto_increment_increment, on each server

auto_increment_offset = 1

Do not bind of any specific IP, use 0.0.0.0 instead:

bind-address = 0.0.0.0

Afterwards we need to restart MySQL for our changes to take effect:

/etc/init.d/mysql restart

Create users

Now we can create the required users. We'll need 3 different users:

functiondescriptionprivilegesmonitor userused by the mmm monitor to check the health of the MySQL serversREPLICATION CLIENTagent userused by the mmm agent to change read-only mode, replication master, etc.SUPER, REPLICATION CLIENT, PROCESSreplication userused for replicationREPLICATION SLAVE

GRANT REPLICATION CLIENT                 ON *.* TO 'mmm_monitor'@'192.168.0.%' IDENTIFIED BY 'monitor_password';GRANT SUPER, REPLICATION CLIENT, PROCESS ON *.* TO 'mmm_agent'@'192.168.0.%'   IDENTIFIED BY 'agent_password';GRANT REPLICATION SLAVE                  ON *.* TO 'replication'@'192.168.0.%' IDENTIFIED BY 'replication_password';

Note: We could be more restrictive here regarding the hosts from which the users are allowed to connect: mmm_monitor is used from 192.168.0.10. mmm_agent and replication are used from 192.168.0.11 - 192.168.0.14.

Note: Don't use a replication_password longer than 32 characters

Synchronisation of data between both databases

I'll assume that db1 contains the correct data. If you have an empty database, you still have to syncronize the accounts we have just created.

First make sure that no one is altering the data while we create a backup.

(db1) mysql> FLUSH TABLES WITH READ LOCK;

Then get the current position in the binary-log. We will need this values when we setup the replication on db2, db3 and db4.

(db1) mysql> SHOW MASTER STATUS;+------------------+----------+--------------+------------------+| File             | Position | Binlog_Do_DB | Binlog_Ignore_DB |+------------------+----------+--------------+------------------+ | mysql-bin.000002 |      374 |              |                  | +------------------+----------+--------------+------------------+ 1 row in set (0.00 sec) 

DON'T CLOSE this mysql-shell. If you close it, the database lock will be removed. Open a second console and type:

db1$ mysqldump -u root -p --all-databases > /tmp/database-backup.sql

Now we can remove the database-lock. Go to the first shell:

(db1) mysql> UNLOCK TABLES;

Copy the database backup to db2, db3 and db4.

db1$ scp /tmp/database-backup.sql <user>@192.168.0.12:/tmpdb1$ scp /tmp/database-backup.sql <user>@192.168.0.13:/tmpdb1$ scp /tmp/database-backup.sql <user>@192.168.0.14:/tmp

Then import this into db2, db3 and db4:

db2$ mysql -u root -p < /tmp/database-backup.sqldb3$ mysql -u root -p < /tmp/database-backup.sqldb4$ mysql -u root -p < /tmp/database-backup.sql

Then flush the privileges on db2, db3 and db4. We have altered the user-table and mysql has to reread this table.

(db2) mysql> FLUSH PRIVILEGES;(db3) mysql> FLUSH PRIVILEGES;(db4) mysql> FLUSH PRIVILEGES;

On debian and ubuntu, copy the passwords in /etc/mysql/debian.cnf from db1 to db2, db3 and db4. This password is used for starting and stopping mysql.

Both databases now contain the same data. We now can setup replication to keep it that way.

Note: Import just only add records from dump file. You shoulddrop all databases before import dump file.

Setup replication

Configure replication on db2, db3 and db4 with the following commands:

(db2) mysql> CHANGE MASTER TO master_host='192.168.0.11', master_port=3306, master_user='replication',               master_password='replication_password', master_log_file='<file>', master_log_pos=<position>;(db3) mysql> CHANGE MASTER TO master_host='192.168.0.11', master_port=3306, master_user='replication',               master_password='replication_password', master_log_file='<file>', master_log_pos=<position>;(db4) mysql> CHANGE MASTER TO master_host='192.168.0.11', master_port=3306, master_user='replication',               master_password='replication_password', master_log_file='<file>', master_log_pos=<position>;

Please insert the values return by “show master status” on db1 at the <file> and <position> tags.

Start the slave-process on all 3 hosts:

(db2) mysql> START SLAVE;(db3) mysql> START SLAVE;(db4) mysql> START SLAVE;

Now check if the replication is running correctly on all hosts:

(db2) mysql> SHOW SLAVE STATUS\G*************************** 1. row ***************************              Slave_IO_State: Waiting for master to send event                 Master_Host: 192.168.0.11                Master_User: replication                Master_Port: 3306               Connect_Retry: 60 …(db3) mysql> SHOW SLAVE STATUS\G*************************** 1. row ***************************              Slave_IO_State: Waiting for master to send event                 Master_Host: 192.168.0.11                Master_User: replication                Master_Port: 3306               Connect_Retry: 60 …(db4) mysql> SHOW SLAVE STATUS\G*************************** 1. row ***************************              Slave_IO_State: Waiting for master to send event                 Master_Host: 192.168.0.11                Master_User: replication                Master_Port: 3306               Connect_Retry: 60 …

Now we have to make db1 replicate from db2. First we have to determine the values for master_log_file and master_log_pos:

(db2) mysql> SHOW MASTER STATUS;+------------------+----------+--------------+------------------+ | File             | Position | Binlog_Do_DB | Binlog_Ignore_DB | +------------------+----------+--------------+------------------+ | mysql-bin.000001 |       98 |              |                  |+------------------+----------+--------------+------------------+ 1 row in set (0.00 sec) 

Now we configure replication on db1 with the following command:

(db1) mysql> CHANGE MASTER TO master_host = '192.168.0.12', master_port=3306, master_user='replication',              master_password='replication_password', master_log_file='<file>', master_log_pos=<position>;

Now insert the values return by “show master status” on db2 at the <file> and <position> tags.

Start the slave-process:

(db1) mysql> START SLAVE;

Now check if the replication is running correctly on db1:

(db1) mysql> SHOW SLAVE STATUS\G*************************** 1. row ***************************              Slave_IO_State: Waiting for master to send event                 Master_Host: 192.168.0.12                Master_User: <replication>                Master_Port: 3306               Connect_Retry: 60 …

Replication between the nodes should now be complete. Try it by inserting some data into both db1 and db2 and check that the data will appear on all other nodes.

Install MMM

Create user

Optional: Create user that will be the owner of the MMM scripts and configuration files. This will provide an easier method to securely manage the monitor scripts.

useradd --comment "MMM Script owner" --shell /sbin/nologin mmmd

Monitoring host

First install dependencies:

aptitude install liblog-log4perl-perl libmailtools-perl liblog-dispatch-perl libclass-singleton-perl libproc-daemon-perl libalgorithm-diff-perl libdbi-perl libdbd-mysql-perl

Then fetch the latest mysql-mmm-common*.deb and mysql-mmm-monitor*.deb and install it:

dpkg -i mysql-mmm-common_*.deb mysql-mmm-monitor*.deb

Database hosts

On UbuntuFirst install dependencies:

aptitude install liblog-log4perl-perl libmailtools-perl liblog-dispatch-perl iproute libnet-arp-perl libproc-daemon-perl libalgorithm-diff-perl libdbi-perl libdbd-mysql-perl

Then fetch the latest mysql-mmm-common*.deb and mysql-mmm-agent*.deb and install it:

dpkg -i mysql-mmm-common_*.deb mysql-mmm-agent_*.deb

On RedHat

yum install -y mysql-mmm-agent

This will take care of all the dependencies, which may include:

Installed:

mysql-mmm-agent.noarch 0:2.2.1-1.el5                                          

Dependency Installed:

libart_lgpl.x86_64 0:2.3.17-4                                                 mysql-mmm.noarch 0:2.2.1-1.el5                                                perl-Algorithm-Diff.noarch 0:1.1902-2.el5                                     perl-DBD-mysql.x86_64 0:4.008-1.rf                                            perl-DateManip.noarch 0:5.44-1.2.1                                            perl-IPC-Shareable.noarch 0:0.60-3.el5                                        perl-Log-Dispatch.noarch 0:2.20-1.el5                                         perl-Log-Dispatch-FileRotate.noarch 0:1.16-1.el5                              perl-Log-Log4perl.noarch 0:1.13-2.el5                                         perl-MIME-Lite.noarch 0:3.01-5.el5                                            perl-Mail-Sender.noarch 0:0.8.13-2.el5.1                                      perl-Mail-Sendmail.noarch 0:0.79-9.el5.1                                      perl-MailTools.noarch 0:1.77-1.el5                                            perl-Net-ARP.x86_64 0:1.0.6-2.1.el5                                           perl-Params-Validate.x86_64 0:0.88-3.el5                                      perl-Proc-Daemon.noarch 0:0.03-1.el5                                          perl-TimeDate.noarch 1:1.16-5.el5                                             perl-XML-DOM.noarch 0:1.44-2.el5                                              perl-XML-Parser.x86_64 0:2.34-6.1.2.2.1                                       perl-XML-RegExp.noarch 0:0.03-2.el5                                           rrdtool.x86_64 0:1.2.27-3.el5                                                 rrdtool-perl.x86_64 0:1.2.27-3.el5 

Configure MMM

All generic configuration-options are grouped in a separate file called /etc/mysql-mmm/mmm_common.conf. This file will be the same on all hosts in the system:

active_master_role          writer<host default>    cluster_interface       eth0    pid_path                /var/run/mmmd_agent.pid    bin_path                /usr/lib/mysql-mmm/    replication_user        replication    replication_password    replication_password    agent_user              mmm_agent    agent_password          agent_password</host><host db1>    ip                      192.168.0.11    mode                    master    peer                    db2</host><host db2>    ip                      192.168.0.12    mode                    master    peer                    db1</host><host db3>    ip                      192.168.0.13    mode                    slave</host><host db4>    ip                      192.168.0.14    mode                    slave</host><role writer>    hosts                   db1, db2    ips                     192.168.0.100    mode                    exclusive</role><role reader>    hosts                   db1, db2, db3, db4    ips                     192.168.0.101, 192.168.0.102, 192.168.0.103, 192.168.0.104    mode                    balanced</role>

Don't forget to copy this file to all other hosts (including the monitoring host).

On the database hosts we need to edit /etc/mysql-mmm/mmm_agent.conf. Change “db1” accordingly on the other hosts:

include mmm_common.confthis db1

On the monitor host we need to edit /etc/mysql-mmm/mmm_mon.conf:

include mmm_common.conf<monitor>    ip                      127.0.0.1    pid_path                /var/run/mmmd_mon.pid    bin_path                /usr/lib/mysql-mmm/    status_path             /var/lib/misc/mmmd_mon.status    ping_ips                192.168.0.1, 192.168.0.11, 192.168.0.12, 192.168.0.13, 192.168.0.14</monitor><host default>    monitor_user            mmm_monitor    monitor_password        monitor_password</host>debug 0

ping_ips are some ips that are pinged to determine whether the network connection of the monitor is ok. I used my switch (192.168.0.1) and the four database server.

Start MMM

Start the agents

(On the database hosts)

Debian/Ubuntu

Edit /etc/default/mysql-mmm-agent to enable the agent:

ENABLED=1

Red Hat

RHEL/Fedora does not enable packages to start at boot time per default policy, so you might have to turn it on manually so the agents will start automatically when server is rebooted:

chkconfig mysql-mmm-agent on

Then start it:

/etc/init.d/mysql-mmm-agent start

Start the monitor

(On the monitoring host)Edit /etc/default/mysql-mmm-monitor to enable the monitor:

ENABLED=1

Then start it:

/etc/init.d/mysql-mmm-monitor start

Wait some seconds for mmmd_mon to start up. After a few seconds you can use mmm_control to check the status of the cluster:

mon$ mmm_control show  db1(192.168.0.11) master/AWAITING_RECOVERY. Roles:   db2(192.168.0.12) master/AWAITING_RECOVERY. Roles:   db3(192.168.0.13) slave/AWAITING_RECOVERY. Roles:   db4(192.168.0.14) slave/AWAITING_RECOVERY. Roles: 

Because its the first startup the monitor does not know our hosts, so it sets all hosts to state AWAITING_RECOVERY and logs a warning message:

mon$ tail /var/log/mysql-mmm/mmm_mon.warn…2009/10/28 23:15:28  WARN Detected new host 'db1': Setting its initial state to 'AWAITING_RECOVERY'. Use 'mmm_control set_online db1' to switch it online.2009/10/28 23:15:28  WARN Detected new host 'db2': Setting its initial state to 'AWAITING_RECOVERY'. Use 'mmm_control set_online db2' to switch it online.2009/10/28 23:15:28  WARN Detected new host 'db3': Setting its initial state to 'AWAITING_RECOVERY'. Use 'mmm_control set_online db3' to switch it online.2009/10/28 23:15:28  WARN Detected new host 'db4': Setting its initial state to 'AWAITING_RECOVERY'. Use 'mmm_control set_online db4' to switch it online.

Now we set or hosts online (db1 first, because the slaves replicate from this host):

mon$ mmm_control set_online db1OK: State of 'db1' changed to ONLINE. Now you can wait some time and check its new roles!mon$ mmm_control set_online db2OK: State of 'db2' changed to ONLINE. Now you can wait some time and check its new roles!mon$ mmm_control set_online db3OK: State of 'db3' changed to ONLINE. Now you can wait some time and check its new roles!mon$ mmm_control set_online db4OK: State of 'db4' changed to ONLINE. Now you can wait some time and check its new roles!

mmm2/guide.txt · Last modified: 2012-11-21 01:27 by Valerie Parham-Thompson