MGR single master startup error processing ERROR 3092

Environment description:

Three-node MGR cluster, single master mode, ready to shut down the primary node for database maintenance, there is an error message.

1. Close the database mysql > shutdown Query OK 0 rows affected (0.00 sec) mysql > mysql > 2019-09-23T07:16:36.262422Z mysqld_safe mysqld from pid file / data/arkdb/3306/pid/mysql.pid ended2, Start the database [root@localhost ~] # mysqld_safe-- defaults-file=/data/arkdb/3306/etc/my.cnf & [1] 21806 [root@localhost ~] # mysqld_safe Adding'/ usr/lib64/libjemalloc.so.1' to LD_PRELOAD for mysqld2019-09-23T07:17:32.239260Z mysqld_safe Logging to'/ data/arkdb/3306/log/mysql-error.log'.2019-09-23T07:17:32.287687Z mysqld_safe Starting mysqld daemon with databases from / data/arkdb/3306/data3, Start group replication mysql > start group_replication ERROR 3092 (HY000): The server is not configured properly to be an active member of the group. Please see more details on error log.4, check the error message grep ERROR mysql-error.log2019-09-23T07:18:10.080941Z 0 [ERROR] Plugin group_replication reported: 'The member configuration is not compatible with the group configuration. Variables such as single_primary_mode or enforce_update_everywhere_checks must have the same value on every server in the group. (member configuration option: [], group configuration option: [group_replication_single_primary_mode]).'5. View the parameter mysql > show variables like'% single%' +-- +-+ | Variable_name | Value | +-- +-+ | group_replication_single _ primary_mode | OFF | +-- +-+ 1 row in set (0.00 sec) mysql > show variables like'% enforce_update_everywhere_checks' +-+-+ | Variable_name | Value | +-- -+-+ | group_replication_enforce_update_everywhere_checks | OFF | +-+-+ 1 row in set (0.01 sec) 6. Start single main mode Then this startup group replicates mysql > set global group_replication_single_primary_mode=on Query OK, 0 rows affected (0.00 sec) mysql > show variables like'% single%' +-- +-+ | Variable_name | Value | +-- +-+ | group_replication_single _ primary_mode | ON | +-- +-+ 1 row in set (0.01sec) mysql > start group_replication Query OK, 0 rows affected (3.26 sec) mysql > 7, Verification mysql > select * from performance_schema.replication_group_members +-+ | CHANNEL_NAME | | MEMBER_ID | MEMBER_HOST | MEMBER_PORT | MEMBER_STATE | +-- | -+-+ | group_replication_applier | 500dd0aa-b8f6-11e9-85ba-005056875a61 | 196.55.x.xxx | 3306 | ONLINE | | group_replication_applier | 59d7f183-b8f6-11e9-863b-005056875165 | 196.55.x.xxx | 3306 | ONLINE | | group_replication_applier | 69e1c26d-b8f6-11e9-91c1-00505687032a | 196.55.x.xxx | 3306 | ONLINE | +- -+-- + 3 rows in set (0.00 sec)