我执行了以下操作来从备份恢复故障节点并能够恢复集群状态。
1）下面是其中一个节点发生故障（NODE01）时集群的状态。
MySQL NODE02:3306 ssl JS > var c=dba.getCluster()
MySQL NODE02:3306 ssl JS > c.status()
{
"clusterName": "QACluster",
"defaultReplicaSet": {
"name": "default",
"primary": "NODE03:3306",
"ssl": "REQUIRED",
"status": "OK_NO_TOLERANCE",
"statusText": "Cluster is NOT tolerant to any failures. 1 member is not active",
"topology": {
"NODE02:3306": {
"address": "NODE02:3306",
"mode": "R/O",
"readReplicas": {},
"role": "HA",
"status": "ONLINE"
},
"NODE03:3306": {
"address": "NODE03:3306",
"mode": "R/W",
"readReplicas": {},
"role": "HA",
"status": "ONLINE"
},
"NODE01:3306": {
"address": "NODE01:3306",
"mode": "R/O",
"readReplicas": {},
"role": "HA",
"status": "(MISSING)"
}
}
},
"groupInformationSourceMember": "mysql://clusterAdmin@NODE03:3306"
}
2) 使用以下命令从主节点（健康节点）获取mysqldump。
[root@NODE03 db_backup]# mysqldump --all-databases --add-drop-database --single-transaction --triggers --routines --port=mysql_port --user=root -p > /db_backup/mysql_dump_03062019.sql
Enter password:
Warning: A partial dump from a server that has GTIDs will by default include the GTIDs of all transactions, even those that changed suppressed parts of the database. If you don't want to restore GTIDs, pass --set-gtid-purged=OFF. To make a complete dump, pass --all-databases --triggers --routines --events.
3) 执行以下步骤从集群中删除故障节点。
MySQL NODE03:3306 ssl JS > var c=dba.getCluster()
MySQL NODE03:3306 ssl JS > c.rescan()
Rescanning the cluster...
Result of the rescanning operation:
{
"defaultReplicaSet": {
"name": "default",
"newlyDiscoveredInstances": [],
"unavailableInstances": [
{
"host": "NODE01:3306",
"label": "NODE01:3306",
"member_id": "e2aa897d-1828-11e9-85b3-00505692188c"
}
]
}
}
The instance 'NODE01:3306' is no longer part of the HA setup. It is either offline or left the HA group.
You can try to add it to the cluster again with the cluster.rejoinInstance('NODE01:3306') command or you can remove it from the cluster configuration.
Would you like to remove it from the cluster metadata? [Y/n]: Y
Removing instance from the cluster metadata...
The instance 'NODE01:3306' was successfully removed from the cluster metadata.
MySQL NODE03:3306 ssl JS > c.status()
{
"clusterName": "QACluster",
"defaultReplicaSet": {
"name": "default",
"primary": "NODE03:3306",
"ssl": "REQUIRED",
"status": "OK_NO_TOLERANCE",
"statusText": "Cluster is NOT tolerant to any failures.",
"topology": {
"NODE02:3306": {
"address": "NODE02:3306",
"mode": "R/O",
"readReplicas": {},
"role": "HA",
"status": "ONLINE"
},
"NODE03:3306": {
"address": "NODE03:3306",
"mode": "R/W",
"readReplicas": {},
"role": "HA",
"status": "ONLINE"
}
}
},
"groupInformationSourceMember": "mysql://clusterAdmin@NODE03:3306"
}
4) 如果组复制仍在故障节点上运行，则停止组复制。
mysql> STOP GROUP_REPLICATION;
Query OK, 0 rows affected (1.01 sec)
5) 在故障节点上重置“gtid_execulated”。
mysql> show global variables like 'GTID_EXECUTED';
+---------------+--------------------------------------------------------------------------------------------+
| Variable_name | Value |
+---------------+--------------------------------------------------------------------------------------------+
| gtid_executed | 01f27b9c-182a-11e9-a199-00505692188c:1-14134172,
e2aa897d-1828-11e9-85b3-00505692188c:1-12 |
+---------------+--------------------------------------------------------------------------------------------+
1 row in set (0.01 sec)
mysql> reset master;
Query OK, 0 rows affected (0.02 sec)
mysql> reset slave;
Query OK, 0 rows affected (0.02 sec)
mysql> show global variables like 'GTID_EXECUTED';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| gtid_executed | |
+---------------+-------+
1 row in set (0.00 sec)
6) 在故障节点上禁用“super_readonly_flag”。
mysql> SELECT @@global.read_only, @@global.super_read_only;
+--------------------+--------------------------+
| @@global.read_only | @@global.super_read_only |
+--------------------+--------------------------+
| 1 | 1 |
+--------------------+--------------------------+
1 row in set (0.00 sec)
mysql> SET GLOBAL super_read_only = 0;
Query OK, 0 rows affected (0.00 sec)
mysql> SELECT @@global.read_only, @@global.super_read_only;
+--------------------+--------------------------+
| @@global.read_only | @@global.super_read_only |
+--------------------+--------------------------+
| 1 | 0 |
+--------------------+--------------------------+
1 row in set (0.00 sec)
7) 将 mysqldump 从 master 恢复到故障节点。
[root@E2LXQA1ALFDB01 db_backup]# mysql -uroot -p < mysql_dump_03062019.sql
8) 恢复完成后，在故障节点上启用“super_readonly_flag”。
mysql> SELECT @@global.read_only, @@global.super_read_only;
+--------------------+--------------------------+
| @@global.read_only | @@global.super_read_only |
+--------------------+--------------------------+
| 1 | 0 |
+--------------------+--------------------------+
1 row in set (0.00 sec)
mysql> SET GLOBAL super_read_only = 1;
Query OK, 0 rows affected (0.00 sec)
mysql> SELECT @@global.read_only, @@global.super_read_only;
+--------------------+--------------------------+
| @@global.read_only | @@global.super_read_only |
+--------------------+--------------------------+
| 1 | 1 |
+--------------------+--------------------------+
1 row in set (0.00 sec)
9) 最后将故障节点添加回innodb集群。
MySQL NODE03:3306 ssl JS > c.addInstance('clusterAdmin@NODE01:3306');
A new instance will be added to the InnoDB cluster. Depending on the amount of
data on the cluster this might take from a few seconds to several hours.
Adding instance to the cluster ...
Please provide the password for 'clusterAdmin@NODE01:3306': *******************
Save password for 'clusterAdmin@NODE01:3306'? [Y]es/[N]o/Ne[v]er (default No):
Validating instance at NODE01:3306...
This instance reports its own address as NODE01
WARNING: The following tables do not have a Primary Key or equivalent column:
ephesoft.dlf, report.correction_type, report.field_details_ag, report_archive.correction_type, report_archive.field_details_ag, report_archive.global_data_ag
Group Replication requires tables to use InnoDB and have a PRIMARY KEY or PRIMARY KEY Equivalent (non-null unique key). Tables that do not follow these requirements will be readable but not updateable when used with Group Replication. If your applications make updates (INSERT, UPDATE or DELETE) to these tables, ensure they use the InnoDB storage engine and have a PRIMARY KEY or PRIMARY KEY Equivalent.
Instance configuration is suitable.
WARNING: On instance 'NODE01:3306' membership change cannot be persisted since MySQL version 5.7.24 does not support the SET PERSIST command (MySQL version >= 8.0.11 required). Please use the .configureLocalInstance command locally to persist the changes.
WARNING: On instance 'NODE02:3306' membership change cannot be persisted since MySQL version 5.7.24 does not support the SET PERSIST command (MySQL version >= 8.0.11 required). Please use the .configureLocalInstance command locally to persist the changes.
WARNING: On instance 'NODE03:3306' membership change cannot be persisted since MySQL version 5.7.24 does not support the SET PERSIST command (MySQL version >= 8.0.11 required). Please use the .configureLocalInstance command locally to persist the changes.
The instance 'clusterAdmin@NODE01:3306' was successfully added to the cluster.
MySQL NODE03:3306 ssl JS > c.status()
{
"clusterName": "QACluster",
"defaultReplicaSet": {
"name": "default",
"primary": "NODE03:3306",
"ssl": "REQUIRED",
"status": "OK",
"statusText": "Cluster is ONLINE and can tolerate up to ONE failure.",
"topology": {
"NODE01:3306": {
"address": "NODE01:3306",
"mode": "R/O",
"readReplicas": {},
"role": "HA",
"status": "ONLINE"
},
"NODE02:3306": {
"address": "NODE02:3306",
"mode": "R/O",
"readReplicas": {},
"role": "HA",
"status": "ONLINE"
},
"NODE03:3306": {
"address": "NODE03:3306",
"mode": "R/W",
"readReplicas": {},
"role": "HA",
"status": "ONLINE"
}
}
},
"groupInformationSourceMember": "mysql://clusterAdmin@NODE03:3306"
}
