Xtradb+Haproxy高可用數據庫集羣（一）xtradb部署篇

部署xtradb cluster時，建議使用3臺及以上服務器。緣由有二：

  1、默認狀況下，若是一個同伴死去或者兩個節點之間的通訊不穩定，兩個節點都將不接受查詢。固然這個能夠經過添加忽略仲裁來解決：

set globalwsrep_provider_options=」pc.ignore_quorum=true」;

 

  2、當宕掉的那臺啓動時，會進行同步，負責提供數據的節點角色變爲Donor， Donor會有必定的時間沒法寫入。斷開狀況以下：

    Mysqldump 適合小庫

    Rsync      複製時間內斷開，速度快

    XtraBackup 短期內斷開，速度略慢

節點信息

node #1

hostname:percona1

IP:192.168.70.71

 

node #2

hostname:percona2

IP:192.168.70.72

 

node #3

hostname:percona3

IP:192.168.70.73

 

前提條件：

三個節點都安裝了centos系統

   防火牆放通了端口：3306,4444,4567和4568

   關閉selinux

 

安裝percona xtradb集羣

先安裝percona官方源

yum installhttp://www.percona.com/downloads/percona-release/redhat/0.1-3/percona-release-0.1-3.noarch.rpm

安裝epel源，以便安裝依賴包socat

yum install https://dl.fedoraproject.org/pub/epel/epel-release-latest-6.noarch.rpm

安裝xtradb

yum installPercona-XtraDB-Cluster-56

 

官網安裝參考地址：

https://www.percona.com/doc/percona-xtradb-cluster/5.6/installation/yum_repo.html

 

配置節點

官網參考地址：

https://www.percona.com/doc/percona-xtradb-cluster/5.6/howtos/virt_sandbox.html

 

配置第一個節點

第一個節點的/etc/my.cnf配置內容以下：

[mysqld]

 

datadir=/var/lib/mysql

user=mysql

 

# Path to Galeralibrary

wsrep_provider=/usr/lib64/libgalera_smm.so

 

# Clusterconnection URL contains the IPs of node#1, node#2 and node#3

wsrep_cluster_address=gcomm://192.168.70.71,192.168.70.72,192.168.70.73

 

# In order forGalera to work correctly binlog format should be ROW

binlog_format=ROW

 

# MyISAM storageengine has only experimental support

default_storage_engine=InnoDB

 

# This changeshow InnoDB autoincrement locks are managed and is a requirement for Galera

innodb_autoinc_lock_mode=2

 

# Node #1address

wsrep_node_address=192.168.70.71

 

# SST method

wsrep_sst_method=xtrabackup-v2

 

# Cluster name

wsrep_cluster_name=my_centos_cluster

 

# Authenticationfor SST method

wsrep_sst_auth="sstuser:s3cret"

 

在此以後，第一個節點能夠啓動如下命令：

[root@percona1 ~]#/etc/init.d/mysql bootstrap-pxc

若是在centos7上運行本教程，系統服務以下：

[root@percona1 ~]#  systemctl start mysql@bootstrap.service

 

此命令將啓動集羣初步wsrep_cluster_address設置爲gcomm://。這樣的集羣將自舉以防後面的節點或MySQL從新開始，這不須要改變該配置文件。

 

第一個節點啓動後，集羣狀態檢測：

mysql> show status like 'wsrep%';

+----------------------------+--------------------------------------+

| Variable_name              |Value                                |

+----------------------------+--------------------------------------+

| wsrep_local_state_uuid     | c2883338-834d-11e2-0800-03c9c68e41ec |

...

| wsrep_local_state          | 4                                    |

| wsrep_local_state_comment  | Synced                               |

...

| wsrep_cluster_size         | 1                                    |

| wsrep_cluster_status       | Primary                              |

| wsrep_connected            |ON                                   |

...

| wsrep_ready                |ON                                   |

+----------------------------+--------------------------------------+

40 rows in set (0.01 sec)

該輸出顯示集羣已成功自舉

 

 

修改root密碼，以及刪除空用戶

UPDATE mysql.user SET password=PASSWORD("Passw0rd")where user='root';

delete from mysql.user whereuser='';

FLUSH PRIVILEGES;

 

 

爲了使xtrabackup成功創建快照，須要給新用戶創建適當的權限。

mysql@percona1> CREATE USER'sstuser'@'localhost' IDENTIFIED BY 's3cret';

mysql@percona1> GRANT RELOAD,LOCK TABLES, REPLICATION CLIENT ON *.* TO 'sstuser'@'localhost';

mysql@percona1> FLUSH PRIVILEGES;

注：MySQL的root帳戶也可用於創建PerconaXtrabackup的SST，但建議使用不一樣用戶作這一點。

 

配置第二個節點

第二個節點的/etc/my.cnf配置內容以下：

 

[mysqld]

 

datadir=/var/lib/mysql

user=mysql

 

# Path to Galera library

wsrep_provider=/usr/lib64/libgalera_smm.so

 

# Cluster connection URLcontains IPs of node#1, node#2 and node#3

wsrep_cluster_address=gcomm://192.168.70.71,192.168.70.72,192.168.70.73

 

# In order for Galera to workcorrectly binlog format should be ROW

binlog_format=ROW

 

# MyISAM storage engine hasonly experimental support

default_storage_engine=InnoDB

 

# This changes how InnoDBautoincrement locks are managed and is a requirement for Galera

innodb_autoinc_lock_mode=2

 

# Node #2 address

wsrep_node_address=192.168.70.72

 

# Cluster name

wsrep_cluster_name=my_centos_cluster

 

# SST method

wsrep_sst_method=xtrabackup-v2

 

#Authentication for SSTmethod

wsrep_sst_auth="sstuser:s3cret"

 

第二個節點的啓動命令

/etc/init.d/mysql start

 

服務器已經啓動後，它會自動接收狀態快照傳送。所以，第二個節點不會有空root密碼了。

 

 

這是第二個節點的狀態

mysql> show status like 'wsrep%';

+----------------------------+--------------------------------------+

| Variable_name             | Value                               |

+----------------------------+--------------------------------------+

| wsrep_local_state_uuid    | c2883338-834d-11e2-0800-03c9c68e41ec |

...

| wsrep_local_state         | 4                                   |

| wsrep_local_state_comment | Synced                              |

...

| wsrep_cluster_size        | 2                                   |

| wsrep_cluster_status      | Primary                             |

| wsrep_connected           | ON                                  |

...

| wsrep_ready               | ON                                  |

+----------------------------+--------------------------------------+

40 rows in set (0.01 sec)

 

 

配置第三個節點

第三個節點的/etc/my.cnf配置文件

[mysqld]

 

datadir=/var/lib/mysql

user=mysql

 

# Path to Galera library

wsrep_provider=/usr/lib64/libgalera_smm.so

 

# Cluster connection URLcontains IPs of node#1, node#2 and node#3

wsrep_cluster_address=gcomm://192.168.70.71,192.168.70.72,192.168.70.73

 

# In order for Galera to workcorrectly binlog format should be ROW

binlog_format=ROW

 

# MyISAM storage engine hasonly experimental support

default_storage_engine=InnoDB

 

# This changes how InnoDBautoincrement locks are managed and is a requirement for Galera

innodb_autoinc_lock_mode=2

 

# Node #3 address

wsrep_node_address=192.168.70.73

 

# Cluster name

wsrep_cluster_name=my_centos_cluster

 

# SST method

wsrep_sst_method=xtrabackup-v2

 

#Authentication for SSTmethod

wsrep_sst_auth="sstuser:s3cret"

 

而後啓動節點

/etc/init.d/mysql start

 

服務器已經啓動後，它會自動接收狀態快照傳送。

 

集羣狀態查看：

mysql> show status like 'wsrep%';

+----------------------------+--------------------------------------+

| Variable_name             | Value                               |

+----------------------------+--------------------------------------+

| wsrep_local_state_uuid    | c2883338-834d-11e2-0800-03c9c68e41ec |

...

| wsrep_local_state         | 4                                   |

| wsrep_local_state_comment | Synced                              |

...

| wsrep_cluster_size        | 3                                   |

| wsrep_cluster_status      | Primary                             |

| wsrep_connected           | ON                                  |

...

| wsrep_ready               | ON                                  |

+----------------------------+--------------------------------------+

40 rows in set (0.01 sec)

該輸出證明了第三個節點加入集羣。

 

測試複製

 

在節點2上建立數據庫

mysql@percona2> CREATE DATABASE percona;

Query OK, 1row affected(0.01 sec)

 

在節點3上建立表

mysql@percona3> USE percona;

Database changed

 

mysql@percona3> CREATE TABLE example (node_id INT PRIMARY KEY, node_name VARCHAR(30));

Query OK, 0rows affected(0.05 sec)

 

在節點1上插入數據

mysql@percona1> INSERT INTO percona.example VALUES (1, 'percona1');

QueryOK, 1 rowaffected (0.02 sec)

 

在第二個節點上查看數據

mysql@percona2> SELECT * FROM percona.example;

+---------+-----------+

| node_id | node_name |

+---------+-----------+

|       1 | percona1  |

+---------+-----------+

1 row in set (0.00 sec)

 

集羣搭建完成