一些名詞介紹：
WS：write set 寫數據集
IST: Incremental State Transfer 增量同步
SST：State Snapshot Transfer 全量同步
pxc環境所涉及的端口：
#mysql實例端口
1. Regular MySQL port, default 3306.
#pxc cluster相互通訊的端口
2. Port for group communication, default 4567. It can be changed by the option:
wsrep_provider_options ="gmcast.listen_addr=tcp://0.0.0.0:4010; "
#用於SST傳送的端口
3. Port for State Transfer, default 4444. It can be changed by the option:
wsrep_sst_receive_address=10.11.12.205:5555
#用於IST傳送的端口
4. Port for Incremental State Transfer, default port for group communication + 1 (4568). It can be changed by the option:
wsrep_provider_options = "ist.recv_addr=10.11.12.206:7777; "
搭建步驟：
一、環境情況：
node1:192.168.1.81:6000
node2:192.168.1.240:6000
node3:192.168.1.241:6000
二、防火牆設置：
-A INPUT -m state --state NEW -m tcp -p tcp --dport 3306 -j ACCEPT #本實驗需要改為6000 -A INPUT -m state --state NEW -m tcp -p tcp --dport 4444 -j ACCEPT #本實驗需要改為6020 -A INPUT -m state --state NEW -m tcp -p tcp --dport 4567 -j ACCEPT #本實驗需要改為6030 -A INPUT -m state --state NEW -m tcp -p tcp --dport 4568 -j ACCEPT #本實驗需要改為6031
setenforce 0
二、下載安裝，在node1,node2,node3分別進行如下安裝
yum install -y http://www.percona.com/downloads/percona-release/redhat/0.1-3/percona-release-0.1-3.noarch.rpm yum install -y perl-DBD-MySQL.x86_64 perl-IO-Socket-SSL.noarch socat.x86_64 nc yum install -y openssl openssl-devel #step 1 prepare :5.6.26 needs libssl.so.6 libcrypto.so.6 () cd /usr/lib64 ln -s libssl.so.1.0.1e libssl.so.6 ln -s libcrypto.so.1.0.1e libcrypto.so.6 #step2:download pxc cd /usr/local/src wget https://www.percona.com/downloads/Percona-XtraDB-Cluster-56/Percona-XtraDB-Cluster-5.6.26-25.12/binary/tarball/Percona-XtraDB-Cluster-5.6.26-rel74.0-25.12.1.Linux.x86_64.tar.gz cd /usr/local mv Percona-XtraDB-Cluster-5.6.26-rel74.0-25.12.1.Linux.x86_64.tar.gz pxc_56 #step3:install pxc cd /usr/local/pxc_56
./scripts/mysql_install_db --defaults-file=/home/mysql/my6000.cnf --basedir=/usr/local/pxc_56
chown -R mysql. /home/mysql
chown -R mysql. /usr/local/pxc_56
配置文件：my6000.cnf
[client]
port = 6000 socket = /home/mysql/I6000/mysql.sock default-character-set=utf8 [mysqld] basedir = /usr/local/pxc_56 datadir = /home/mysql/I6000 pid-file = /home/mysql/I6000/mysql.pid character-set-server=utf8 init_connect = 'SET NAMES utf8' log-bin=/home/mysql/I6000/log_bin server-id = 9816000 innodb_buffer_pool_size = 100M innodb_data_file_path = ibdata1:10M:autoextend innodb_data_home_dir = /home/mysql/I6000 innodb_file_per_table=1 skip-name-resolve port = 6000 socket = /home/mysql/I6000/mysql.sock user=mysql log_error=/home/mysql/I6000/mysql_error.log #pxc user=mysql log_error=error.log binlog_format=ROW #6000 for mysqld port, 6020 for sst port, 6031 for ist port, 6030 for cluster communication port 端口作用及說明見上面 wsrep_cluster_address='gcomm://192.168.1.81:6030,192.168.1.238:6030,192.168.1.240:6030' #三個節點都保持一樣 wsrep_provider=/usr/local/pxc_56/lib/libgalera_smm.so wsrep_sst_receive_address=192.168.1.238:6020 #根據不同的node ip進行修改 wsrep_node_incoming_address=192.168.1.238:6000 #根據不同的node ip進行修改 wsrep_node_address=192.168.1.238:6000 #根據不同的node ip進行修改 wsrep_provider_options = "gmcast.listen_addr=tcp://192.168.1.238:6030;ist.recv_addr=192.168.1.238:6031;" #根據不同的node ip進行修改 wsrep_slave_threads=2 wsrep_cluster_name=pxc_zejin #同一個cluster此值需要一致 wsrep_sst_method=xtrabackup-v2 wsrep_node_name=node6000_238 #不同節點修改為不同的名字 innodb_autoinc_lock_mode=2 wsrep_sst_auth="sstuser:123" log-slave-updates [mysql] no-auto-rehash default-character-set=utf8
三、實例啟動：
#安裝實例 /usr/local/pxc_56/scripts/mysql_install_db --defaults-file=/home/mysql/my6000.cnf --basedir=/usr/local/pxc_56 #啟動第一個實例 /usr/local/pxc_56/bin/mysqld_safe --defaults-file=/home/mysql/my6000.cnf --ledir=/usr/local/pxc_56/bin/ --wsrep-new-cluster & #修改密碼 /usr/local/pxc_56/bin/mysqladmin -u root -P6000 password '000000' -S /home/mysql/I6000/mysql.sock #登陸並增加用戶 /usr/local/pxc_56/bin/mysql -uroot -p -P6000 -S /home/mysql/I6000/mysql.sock grant all on *.* to 'sstuser'@'localhost' identified by '123'; flush privielges;
mysql> show global status like 'wsrep_cluster_size'; +--------------------+-------+ | Variable_name | Value | +--------------------+-------+ | wsrep_cluster_size | 1 | +--------------------+-------+ 1 row in set (0.00 sec)
四、啟動第二、三個node
#不需要加--wsrep-new-cluster /usr/local/pxc_56/bin/mysqld_safe --defaults-file=/home/mysql/I6000/my6000.cnf --ledir=/usr/local/pxc_56/bin/ &
整個過程大約如下：
1.決斷是否可以IST
2.不可以的話Requesting state transfer
3.Cleaning the existing datadir and innodb-data/log directories 會將之前實例的內容全部刪除。#所以不能將my6000.cnf文件放在與datadir目錄下，要不會被刪除，並且在重新啟動服務時出錯
4.Waiting for SST streaming to complete
5.啟動服務。
官方說明：
XtraBackup SST works in two stages:
• Stage I on joiner checks if it is SST or IST based on presence of xtrabackup_ist file.
• In Stage II it starts the data transfer, if it’s SST, it empties the data directory sans few files (galera.cache, sst_in_progress, grastate.dat) and then proceed with the SST or if it’s IST, proceeds as before.
• Stage I on joiner checks if it is SST or IST based on presence of xtrabackup_ist file.
• In Stage II it starts the data transfer, if it’s SST, it empties the data directory sans few files (galera.cache, sst_in_progress, grastate.dat) and then proceed with the SST or if it’s IST, proceeds as before.
加入成功： 07:49:13 root@127.0.0.1:[test] 6000>show global status like 'wsrep_cluster_size'; +--------------------+-------+ | Variable_name | Value | +--------------------+-------+ | wsrep_cluster_size | 3 | +--------------------+-------+ 1 row in set (0.00 sec)
五、操作過程中經常用到的命令：
安裝：/usr/local/pxc_56/scripts/mysql_install_db --defaults-file=/home/mysql/my6000.cnf --basedir=/usr/local/pxc_56 啟動：/usr/local/pxc_56/bin/mysqld_safe --defaults-file=/home/mysql/my6000.cnf --ledir=/usr/local/pxc_56/bin/ & ( 第一個節點要加上--wsrep-new-cluster ) 登陸：/usr/local/pxc_56/bin/mysql -uroot -p -P6000 -S /home/mysql/I6000/mysql.sock 關閉：/usr/local/pxc_56/bin/mysqladmin -uroot -p -P6000 -S /home/mysql/I6000/mysql.sock shutdown
六、安裝過程中可能遇到的問題：
A.
節點啟動時： /usr/local/pxc_56/bin/mysqld_safe --defaults-file=/home/mysql/my3307.cnf --ledir=/usr/local/pxc_56/bin/ & 有可能啟動會提示： WSREP_SST: [ERROR] socat not found in path: /usr/sbin:/sbin:/usr/local/pxc_56//bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/opt/lamp/mysql/bin:/root/bi n (20160509 10:58:04.404) 2016-05-09 10:58:04 54809 [ERROR] WSREP: Failed to read 'ready <addr>' from: wsrep_sst_xtrabackup-v2 --role 'joiner' --address '192.168.1.238' --datadir '/home/mysql/I3307/ ' --defaults-file '/home/mysql/I3307/my3307.cnf' --defaults-group-suffix '' --parent '54809' '' Read: '(null)' 2016-05-09 10:58:04 54809 [ERROR] WSREP: Process completed with error: wsrep_sst_xtrabackup-v2 --role 'joiner' --address '192.168.1.238' --datadir '/home/mysql/I3307/' --de faults-file '/home/mysql/I3307/my3307.cnf' --defaults-group-suffix '' --parent '54809' '' : 2 (No such file or directory) 2016-05-09 10:58:04 54809 [ERROR] WSREP: Failed to prepare for 'xtrabackup-v2' SST. Unrecoverable. 2016-05-09 10:58:04 54809 [ERROR] Aborting
原因及解決方法：socat 沒有安裝到，之前源包沒有，可以進行如下安裝：
wget --no-cache
http://www.convirture.com/repos/definitions/rhel/6.x/convirt.repo -O /etc/yum.repos.d/convirt.repo
yum install socat
B.
第一個節點如果直接這樣啟動：
/usr/local/pxc_56/bin/mysqld_safe --defaults-file=/home/mysql/my6000.cnf & 在errorlog里面會出現： 2016-05-09 09:49:46 9932 [ERROR] WSREP: failed to open gcomm backend connection: 110: failed to reach primary view: 110 (Connection timed out) at gcomm/src/pc.cpp:connect():162 2016-05-09 09:49:46 9932 [ERROR] WSREP: gcs/src/gcs_core.cpp:gcs_core_open():206: Failed to open backend connection: -110 (Connection timed out) 2016-05-09 09:49:46 9932 [ERROR] WSREP: gcs/src/gcs.cpp:gcs_open():1379: Failed to open channel 'pxc_zejin' at 'gcomm://192.168.1.240,192.168.1.238,192.168.1.81': -110 (Con nection timed out) 2016-05-09 09:49:46 9932 [ERROR] WSREP: gcs connect failed: Connection timed out 2016-05-09 09:49:46 9932 [ERROR] WSREP: wsrep::connect(gcomm://192.168.1.240,192.168.1.238,192.168.1.81) failed: 7 2016-05-09 09:49:46 9932 [ERROR] Aborting 2016-05-09 09:49:46 9932 [Note] WSREP: Service disconnected. 2016-05-09 09:49:47 9932 [Note] WSREP: Some threads may fail to exit. 2016-05-09 09:49:47 9932 [Note] Binlog end 2016-05-09 09:49:47 9932 [Note] /usr/local/pxc_56/bin/mysqld: Shutdown complete
解決方法：第一個節點啟動要加上：--wsrep-new-cluster
/usr/local/pxc_56/bin/mysqld_safe --defaults-file=/home/mysql/my6000.cnf --ledir=/usr/local/pxc_56/bin --wsrep-new-cluster &
C.
#第二個節點或第三個節點啟動報錯： WSREP_SST: [ERROR] Cleanup after exit with status:1 (20160509 19:25:50.483) 2016-05-09 19:25:50 44334 [ERROR] WSREP: Process completed with error: wsrep_sst_xtrabackup-v2 --role 'joiner' --address '192.168.1.240:6020' --datadir '/home/mysql/I6000/' --defaults-file '/home/mysql/I6000/my6000.cnf' --defaults-group-suffix '' --parent '44334' '' : 1 (Operation not permitted) 2016-05-09 19:25:50 44334 [ERROR] WSREP: Failed to read uuid:seqno from joiner script. 2016-05-09 19:25:50 44334 [ERROR] WSREP: SST script aborted with error 1 (Operation not permitted) 2016-05-09 19:25:50 44334 [ERROR] WSREP: SST failed: 1 (Operation not permitted) 2016-05-09 19:25:50 44334 [ERROR] Aborting
原因及解決方法：配置文件my6000.cnf放在與datadir目錄下，在Cleaning the existing datadir階段被刪除，在重啟服務時就會找不到配置文件，在重新啟動服務就會出錯，把配置文件放在非datadir目錄下即可。如/etc/my6000.cnf