这篇文章主要讲解了“怎么解决mysql MGR无法连接主节点的问题”，文中的讲解内容简单清晰，易于学习与理解，下面请大家跟着小编的思路慢慢深入，一起来研究和学习“怎么解决mysql MGR无法连接主节点的问题”吧！
1.现象
2020-07-15T16:36:24.238903+08:00 126 [ERROR] [MY-010584] [Repl] Slave I/O for channel
'group_replication_recovery': error connecting to master 'repl@smdw:12000'
- retry-time: 60 retries: 1 message: Authentication plugin 'caching_sha2_password'
reported error: Authentication requires secure connection. Error_code: MY-002061
2020-07-15T16:36:24.245949+08:00 71 [ERROR] [MY-011582] [Repl] Plugin group_replication reported:
'There was an error when connecting to the donor server.
Please check that group_replication_recovery channel credentials and all MEMBER_HOST
column values of performance_schema.replication_group_members table are correct and DNS resolvable.'
2020-07-15T16:36:24.246011+08:00 71 [ERROR] [MY-011583] [Repl] Plugin group_replication reported: 'For details please check performance_schema.replication_connection_status table and error log messages of Slave I/O for channel group_replication_recovery.'
2020-07-15T16:36:24.246227+08:00 71 [ERROR] [MY-011574] [Repl] Plugin group_replication reported: 'Maximum number of retries when trying to connect to a donor reached. Aborting group replication incremental recovery.'
2020-07-15T16:36:24.246332+08:00 71 [ERROR] [MY-011620] [Repl] Plugin group_replication reported: 'Fatal error during the incremental recovery process of Group Replication. The server will leave the group.'
2020-07-15T16:36:24.246648+08:00 71 [ERROR] [MY-011712] [Repl] Plugin group_replication reported: 'The server was automatically set into read only mode after an error was detected.'2.排查
mysql> select * from performance_schema.replication_group_members;
+---------------------------+--------------------------------------+-------------+-------------+--------------+-------------+----------------+
| CHANNEL_NAME | MEMBER_ID | MEMBER_HOST | MEMBER_PORT | MEMBER_STATE | MEMBER_ROLE | MEMBER_VERSION |
+---------------------------+--------------------------------------+-------------+-------------+--------------+-------------+----------------+
| group_replication_applier | b2d6c335-c4b1-11ea-b3a6-3868dd209ff0 | mdw | 12000 | OFFLINE | | |
+---------------------------+--------------------------------------+-------------+-------------+--------------+-------------+----------------+
1 row in set (0.00 sec)
mysql> select * from performance_schema.replication_connection_status\G;
*************************** 1. row ***************************
CHANNEL_NAME: group_replication_applier
GROUP_NAME: aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa
SOURCE_UUID: aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa
THREAD_ID: NULL
SERVICE_STATE: OFF
COUNT_RECEIVED_HEARTBEATS: 0
LAST_HEARTBEAT_TIMESTAMP: 0000-00-00 00:00:00.000000
RECEIVED_TRANSACTION_SET: aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa:1-26,
b2d6c335-c4b1-11ea-b3a6-3868dd209ff0:1-143778
LAST_ERROR_NUMBER: 0
LAST_ERROR_MESSAGE:
LAST_ERROR_TIMESTAMP: 0000-00-00 00:00:00.000000
LAST_QUEUED_TRANSACTION:
LAST_QUEUED_TRANSACTION_ORIGINAL_COMMIT_TIMESTAMP: 0000-00-00 00:00:00.000000
LAST_QUEUED_TRANSACTION_IMMEDIATE_COMMIT_TIMESTAMP: 0000-00-00 00:00:00.000000
LAST_QUEUED_TRANSACTION_START_QUEUE_TIMESTAMP: 0000-00-00 00:00:00.000000
LAST_QUEUED_TRANSACTION_END_QUEUE_TIMESTAMP: 0000-00-00 00:00:00.000000
QUEUEING_TRANSACTION:
QUEUEING_TRANSACTION_ORIGINAL_COMMIT_TIMESTAMP: 0000-00-00 00:00:00.000000
QUEUEING_TRANSACTION_IMMEDIATE_COMMIT_TIMESTAMP: 0000-00-00 00:00:00.000000
QUEUEING_TRANSACTION_START_QUEUE_TIMESTAMP: 0000-00-00 00:00:00.000000
*************************** 2. row ***************************
CHANNEL_NAME: group_replication_recovery
GROUP_NAME:
SOURCE_UUID:
THREAD_ID: NULL
SERVICE_STATE: OFF
COUNT_RECEIVED_HEARTBEATS: 0
LAST_HEARTBEAT_TIMESTAMP: 0000-00-00 00:00:00.000000
RECEIVED_TRANSACTION_SET:
LAST_ERROR_NUMBER: 2061
LAST_ERROR_MESSAGE: error connecting to master 'repl@smdw:12000' - retry-time: 60 retries: 1 message: Authentication plugin 'caching_sha2_password' reported error: Authentication requires secure connection.
LAST_ERROR_TIMESTAMP: 2020-07-15 16:36:24.238879
LAST_QUEUED_TRANSACTION:
LAST_QUEUED_TRANSACTION_ORIGINAL_COMMIT_TIMESTAMP: 0000-00-00 00:00:00.000000
LAST_QUEUED_TRANSACTION_IMMEDIATE_COMMIT_TIMESTAMP: 0000-00-00 00:00:00.000000
LAST_QUEUED_TRANSACTION_START_QUEUE_TIMESTAMP: 0000-00-00 00:00:00.000000
LAST_QUEUED_TRANSACTION_END_QUEUE_TIMESTAMP: 0000-00-00 00:00:00.000000
QUEUEING_TRANSACTION:
QUEUEING_TRANSACTION_ORIGINAL_COMMIT_TIMESTAMP: 0000-00-00 00:00:00.000000
QUEUEING_TRANSACTION_IMMEDIATE_COMMIT_TIMESTAMP: 0000-00-00 00:00:00.000000
QUEUEING_TRANSACTION_START_QUEUE_TIMESTAMP: 0000-00-00 00:00:00.000000
2 rows in set (0.00 sec)
mysql_error.log中显示：
2020-07-15T16:36:24.237434+08:00 126 [Warning] [MY-010897] [Repl] Storing MySQL user name or password information in the master info repository is not secure and is therefore not recommended. Please consider using the USER and PASSWORD connection options for START SLAVE; see the 'START SLAVE Syntax' in the MySQL Manual for more information.
2020-07-15T16:36:24.238903+08:00 126 [ERROR] [MY-010584] [Repl] Slave I/O for channel 'group_replication_recovery': error connecting to master 'repl@smdw:12000' - retry-time: 60 retries: 1 message: Authentication plugin 'caching_sha2_password' reported error: Authentication requires secure connection. Error_code: MY-002061
2020-07-15T16:36:24.245949+08:00 71 [ERROR] [MY-011582] [Repl] Plugin group_replication reported: 'There was an error when connecting to the donor server. Please check that group_replication_recovery channel credentials and all MEMBER_HOST column values of performance_schema.replication_group_members table are correct and DNS resolvable.'
2020-07-15T16:36:24.246011+08:00 71 [ERROR] [MY-011583] [Repl] Plugin group_replication reported: 'For details please check performance_schema.replication_connection_status table and error log messages of Slave I/O for channel group_replication_recovery.'
2020-07-15T16:36:24.246227+08:00 71 [ERROR] [MY-011574] [Repl] Plugin group_replication reported: 'Maximum number of retries when trying to connect to a donor reached. Aborting group replication incremental recovery.'
2020-07-15T16:36:24.246332+08:00 71 [ERROR] [MY-011620] [Repl] Plugin group_replication reported: 'Fatal error during the incremental recovery process of Group Replication. The server will leave the group.'
2020-07-15T16:36:24.246648+08:00 71 [ERROR] [MY-011712] [Repl] Plugin group_replication reported: 'The server was automatically set into read only mode after an error was detected.'3.原因
万事不决看官方文档，官方文档有很明确说明：
Replication User With The Caching SHA-2 Authentication Plugin
By default, users created in MySQL 8 use Section 6.4.1.2, “Caching SHA-2 Pluggable Authentication”.
If the replication user you configure for distributed recovery uses the caching SHA-2 authentication
plugin, and you are not using SSL for distributed recovery connections, RSA key-pairs are used for
password exchange. For more information on RSA key-pairs, see Section 6.3.3, “Creating SSL and
RSA Certificates and Keys”.
In this situation, you can either copy the public key of the rpl_user to the joining member, or
configure the donors to provide the public key when requested. The more secure approach is to copy
the public key of the replication user account to the joining member. Then you need to configure the
group_replication_recovery_public_key_path system variable on the joining member with
the path to the public key for the replication user account.
The less secure approach is to set group_replication_recovery_get_public_key=ON
on donors so that they provide the public key of the replication user account to
joining members. There is no way to verify the identity of a server, therefore only set
group_replication_recovery_get_public_key=ON when you are sure there is no risk of
server identity being compromised, for example by a man-in-the-middle attack可以看到，当确认环境安全以及没人任何人攻击集群时，如果不配置ssl，可以最低配置下面参数来在请求复制用户密钥时
给公钥：
group_replication_recovery_get_public_key=ON4.解决
mysql> start group replication;mysql> start group replication;
mysql> set global group_replication_recovery_get_public_key=on;
mysql> start group replication;5.检查状态
mysql> select * from performance_schema.replication_connection_status\G;
*************************** 1. row ***************************
CHANNEL_NAME: group_replication_applier
GROUP_NAME: aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa
SOURCE_UUID: aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa
THREAD_ID: NULL
SERVICE_STATE: ON
COUNT_RECEIVED_HEARTBEATS: 0
LAST_HEARTBEAT_TIMESTAMP: 0000-00-00 00:00:00.000000
RECEIVED_TRANSACTION_SET: aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa:1-26:29,
b2d6c335-c4b1-11ea-b3a6-3868dd209ff0:1-143778
LAST_ERROR_NUMBER: 0
LAST_ERROR_MESSAGE:
LAST_ERROR_TIMESTAMP: 0000-00-00 00:00:00.000000
LAST_QUEUED_TRANSACTION: aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa:29
LAST_QUEUED_TRANSACTION_ORIGINAL_COMMIT_TIMESTAMP: 0000-00-00 00:00:00.000000
LAST_QUEUED_TRANSACTION_IMMEDIATE_COMMIT_TIMESTAMP: 0000-00-00 00:00:00.000000
LAST_QUEUED_TRANSACTION_START_QUEUE_TIMESTAMP: 2020-07-15 16:47:36.329298
LAST_QUEUED_TRANSACTION_END_QUEUE_TIMESTAMP: 2020-07-15 16:47:36.329384
QUEUEING_TRANSACTION:
QUEUEING_TRANSACTION_ORIGINAL_COMMIT_TIMESTAMP: 0000-00-00 00:00:00.000000
QUEUEING_TRANSACTION_IMMEDIATE_COMMIT_TIMESTAMP: 0000-00-00 00:00:00.000000
QUEUEING_TRANSACTION_START_QUEUE_TIMESTAMP: 0000-00-00 00:00:00.000000
*************************** 2. row ***************************
CHANNEL_NAME: group_replication_recovery
GROUP_NAME:
SOURCE_UUID:
THREAD_ID: NULL
SERVICE_STATE: OFF
COUNT_RECEIVED_HEARTBEATS: 0
LAST_HEARTBEAT_TIMESTAMP: 0000-00-00 00:00:00.000000
RECEIVED_TRANSACTION_SET:
LAST_ERROR_NUMBER: 0
LAST_ERROR_MESSAGE:
LAST_ERROR_TIMESTAMP: 0000-00-00 00:00:00.000000
LAST_QUEUED_TRANSACTION:
LAST_QUEUED_TRANSACTION_ORIGINAL_COMMIT_TIMESTAMP: 0000-00-00 00:00:00.000000
LAST_QUEUED_TRANSACTION_IMMEDIATE_COMMIT_TIMESTAMP: 0000-00-00 00:00:00.000000
LAST_QUEUED_TRANSACTION_START_QUEUE_TIMESTAMP: 0000-00-00 00:00:00.000000
LAST_QUEUED_TRANSACTION_END_QUEUE_TIMESTAMP: 0000-00-00 00:00:00.000000
QUEUEING_TRANSACTION:
QUEUEING_TRANSACTION_ORIGINAL_COMMIT_TIMESTAMP: 0000-00-00 00:00:00.000000
QUEUEING_TRANSACTION_IMMEDIATE_COMMIT_TIMESTAMP: 0000-00-00 00:00:00.000000
QUEUEING_TRANSACTION_START_QUEUE_TIMESTAMP: 0000-00-00 00:00:00.000000
2 rows in set (0.00 sec)
ERROR:
No query specified
mysql>
mysql>
mysql> select * from performance_schema.replication_group_members;
+---------------------------+--------------------------------------+-------------+-------------+--------------+-------------+----------------+
| CHANNEL_NAME | MEMBER_ID | MEMBER_HOST | MEMBER_PORT | MEMBER_STATE | MEMBER_ROLE | MEMBER_VERSION |
+---------------------------+--------------------------------------+-------------+-------------+--------------+-------------+----------------+
| group_replication_applier | 6c48e4d6-c651-11ea-a94d-3868dd209dd0 | smdw | 12000 | ONLINE | PRIMARY | 8.0.20 |
| group_replication_applier | b2d6c335-c4b1-11ea-b3a6-3868dd209ff0 | mdw | 12000 | ONLINE | SECONDARY | 8.0.20 |
+---------------------------+--------------------------------------+-------------+-------------+--------------+-------------+----------------+
2 rows in set (0.00 sec)感谢各位的阅读，以上就是“怎么解决mysql MGR无法连接主节点的问题”的内容了，经过本文的学习后，相信大家对怎么解决mysql MGR无法连接主节点的问题这一问题有了更深刻的体会，具体使用情况还需要大家实践验证。这里是亿速云，小编将为大家推送更多相关知识点的文章，欢迎关注！
