1.單主模式
1.1 模擬主節(jié)點掛掉（xag211）
[root@xag211 ~]# service mysqld stop
root@xag212:testdb [:15: ] 25 SQL->select * from performance_schema.replication_group_members;
+---------------------------+--------------------------------------+-------------+-------------+--------------+
| CHANNEL_NAME | MEMBER_ID | MEMBER_HOST | MEMBER_PORT | MEMBER_STATE |
+---------------------------+--------------------------------------+-------------+-------------+--------------+
| group_replication_applier | 2126c7e9-63c9-11eb-a1ba-000c299e2212 | xag212 | 3306 | ONLINE |
| group_replication_applier | 2136c7e9-63c9-11eb-a1ba-000c299e2213 | xag213 | 3306 | ONLINE |
+---------------------------+--------------------------------------+-------------+-------------+--------------+
root@xag212:testdb [:22: ] 26 SQL->
SELECT ta.* ,tb.MEMBER_HOST,tb.MEMBER_PORT,tb.MEMBER_STATE FROM
performance_schema.global_status ta,performance_schema.replication_group_members tb
WHERE ta.VARIABLE_NAME='group_replication_primary_member' and ta.VARIABLE_VALUE=tb.MEMBER_ID;
+----------------------------------+--------------------------------------+-------------+-------------+--------------+
| VARIABLE_NAME | VARIABLE_VALUE | MEMBER_HOST | MEMBER_PORT | MEMBER_STATE |
+----------------------------------+--------------------------------------+-------------+-------------+--------------+
| group_replication_primary_member | 2126c7e9-63c9-11eb-a1ba-000c299e2212 | xag212 | 3306 | ONLINE |
+----------------------------------+--------------------------------------+-------------+-------------+--------------+
root@xag212:testdb [:22: ] 27 SQL->delete from t1 where Id=2;
Query OK, 1 row affected (0.00 sec)
1.2 原主節(jié)點故障修復（xag211）即啟動
[root@xag211 ~]# service mysqld start
root@xag211:(none) [:26: ] 2 SQL->START GROUP_REPLICATION;
root@xag211:(none) [:26: ] 3 SQL->
select * from performance_schema.replication_group_members;
+---------------------------+--------------------------------------+-------------+-------------+--------------+
| CHANNEL_NAME | MEMBER_ID | MEMBER_HOST | MEMBER_PORT | MEMBER_STATE |
+---------------------------+--------------------------------------+-------------+-------------+--------------+
| group_replication_applier | 2116c7e9-63c9-11eb-a1ba-000c299e2211 | xag211 | 3306 | ONLINE |
| group_replication_applier | 2126c7e9-63c9-11eb-a1ba-000c299e2212 | xag212 | 3306 | ONLINE |
| group_replication_applier | 2136c7e9-63c9-11eb-a1ba-000c299e2213 | xag213 | 3306 | ONLINE |
+---------------------------+--------------------------------------+-------------+-------------+--------------+
root@xag211:testdb [:27: ] 6 SQL->
select * from t1;
+----+----------+
| Id | TestName |
+----+----------+
| 1 | a |
+----+----------+
2.要是三個節(jié)點都發(fā)生故障的話，在節(jié)點的故障都恢復后蓬推，需要手動重新做組復制畜普，操作流程如下：
第一個節(jié)點
reset master;
SET SQL_LOG_BIN=1;
CHANGE MASTER TO MASTER_USER='repl', MASTER_PASSWORD='repl' FOR CHANNEL 'group_replication_recovery';
STOP GROUP_REPLICATION;
SET GLOBAL group_replication_bootstrap_group=ON;
START GROUP_REPLICATION;
SET GLOBAL group_replication_bootstrap_group=OFF;
SELECT * FROM performance_schema.replication_group_members;
第二個節(jié)點
reset master;
SET SQL_LOG_BIN=1;
CHANGE MASTER TO MASTER_USER='repl', MASTER_PASSWORD='repl' FOR CHANNEL 'group_replication_recovery';
START GROUP_REPLICATION;
第三個節(jié)點
reset master;
SET SQL_LOG_BIN=1;
CHANGE MASTER TO MASTER_USER='repl', MASTER_PASSWORD='repl' FOR CHANNEL 'group_replication_recovery';
START GROUP_REPLICATION;
