此Bug详细日志是：
3月 19 10:24:39 localhost.localdomain mysqld[80382]: 2020-03-19 10:24:39 0 [Warning] WSREP: handshake with 2ca7072e tcp://172.30.251.39:4567 failed: ‘invalid group‘ 3月 19 10:24:40 localhost.localdomain mysqld[80382]: 2020-03-19 10:24:40 0 [Warning] WSREP: handshake with 2ca7072e tcp://172.30.251.39:4567 failed: ‘invalid group‘ 3月 19 10:24:42 localhost.localdomain mysqld[80382]: 2020-03-19 10:24:42 0 [Warning] WSREP: handshake with 2ca7072e tcp://172.30.251.39:4567 failed: ‘invalid group‘ 3月 19 10:24:43 localhost.localdomain mysqld[80382]: 2020-03-19 10:24:43 0 [Warning] WSREP: handshake with 2ca7072e tcp://172.30.251.39:4567 failed: ‘invalid group‘ 3月 19 10:24:45 localhost.localdomain mysqld[80382]: 2020-03-19 10:24:45 0 [Warning] WSREP: handshake with 2ca7072e tcp://172.30.251.39:4567 failed: ‘invalid group‘ 3月 19 10:24:46 localhost.localdomain mysqld[80382]: 2020-03-19 10:24:46 0 [Warning] WSREP: handshake with 2ca7072e tcp://172.30.251.39:4567 failed: ‘invalid group‘ 3月 19 10:24:48 localhost.localdomain mysqld[80382]: 2020-03-19 10:24:48 0 [Warning] WSREP: handshake with 2ca7072e tcp://172.30.251.39:4567 failed: ‘invalid group‘ 3月 19 10:24:49 localhost.localdomain mysqld[80382]: 2020-03-19 10:24:49 0 [Warning] WSREP: handshake with 2ca7072e tcp://172.30.251.39:4567 failed: ‘invalid group‘ 3月 19 10:24:51 localhost.localdomain mysqld[80382]: 2020-03-19 10:24:51 0 [Warning] WSREP: handshake with 2ca7072e tcp://172.30.251.39:4567 failed: ‘invalid group‘ 3月 19 10:24:52 localhost.localdomain mysqld[80382]: 2020-03-19 10:24:52 0 [Warning] WSREP: handshake with 2ca7072e tcp://172.30.251.39:4567 failed: ‘invalid group‘ 3月 19 10:24:54 localhost.localdomain mysqld[80382]: 2020-03-19 10:24:54 0 [Warning] WSREP: handshake with 2ca7072e tcp://172.30.251.39:4567 failed: ‘invalid group‘ 3月 19 10:24:55 localhost.localdomain mysqld[80382]: 2020-03-19 10:24:55 0 [Warning] WSREP: handshake with 2ca7072e tcp://172.30.251.39:4567 failed: ‘invalid group‘ 3月 19 10:24:57 localhost.localdomain mysqld[80382]: 2020-03-19 10:24:57 0 [Warning] WSREP: handshake with 2ca7072e tcp://172.30.251.39:4567 failed: ‘invalid group‘ 3月 19 10:24:58 localhost.localdomain mysqld[80382]: 2020-03-19 10:24:58 0 [Warning] WSREP: handshake with 2ca7072e tcp://172.30.251.39:4567 failed: ‘invalid group‘ 3月 19 10:25:00 localhost.localdomain mysqld[80382]: 2020-03-19 10:25:00 0 [Warning] WSREP: handshake with 2ca7072e tcp://172.30.251.39:4567 failed: ‘invalid group‘ 3月 19 10:25:00 localhost.localdomain mysqld[80382]: 2020-03-19 10:25:00 0 [Note] WSREP: PC protocol downgrade 1 -> 0 3月 19 10:25:00 localhost.localdomain mysqld[80382]: 2020-03-19 10:25:00 0 [Note] WSREP: view((empty)) 3月 19 10:25:00 localhost.localdomain mysqld[80382]: 2020-03-19 10:25:00 0 [ERROR] WSREP: failed to open gcomm backend connection: 110: failed to reach primary view: 110 (Connection timed out 3月 19 10:25:00 localhost.localdomain mysqld[80382]: at gcomm/src/pc.cpp:connect():158 3月 19 10:25:00 localhost.localdomain mysqld[80382]: 2020-03-19 10:25:00 0 [ERROR] WSREP: gcs/src/gcs_core.cpp:gcs_core_open():220: Failed to open backend connection: -110 (Connection timed o 3月 19 10:25:00 localhost.localdomain mysqld[80382]: 2020-03-19 10:25:00 0 [ERROR] WSREP: gcs/src/gcs.cpp:gcs_open():1608: Failed to open channel ‘db_cluster‘ at ‘gcomm://192.30.251.40 3月 19 10:25:00 localhost.localdomain mysqld[80382]: 2020-03-19 10:25:00 0 [ERROR] WSREP: gcs connect failed: Connection timed out 3月 19 10:25:00 localhost.localdomain mysqld[80382]: 2020-03-19 10:25:00 0 [ERROR] WSREP: wsrep::connect(gcomm://) failed: 7 3月 19 10:25:00 localhost.localdomain mysqld[80382]: 2020-03-19 10:25:00 0 [ERROR] Aborting 3月 19 10:25:00 localhost.localdomain systemd[1]: mariadb.service: main process exited, code=exited, status=1/FAILURE 3月 19 10:25:00 localhost.localdomain systemd[1]: Failed to start MariaDB 10.4.12 database server.
此Bug差不多困扰我了一天，经过排查发现是因为主节点配置文件少了一个参数：wsrep_cluster_name=db_cluster
在此谨记配置文件及启动顺序
[galera] # Mandatory settings wsrep_on=ON wsrep_provider=/usr/lib64/galera-4/libgalera_smm.so wsrep_cluster_address="gcomm://192.30.251.40,192.30.251.41,192.30.251.39" wsrep_cluster_name=db_cluster wsrep_node_name=db_192.30.251.41 wsrep_node_address=192.30.251.41 wsrep_sst_method=rsync binlog_format=row default_storage_engine=InnoDB innodb_autoinc_lock_mode=2
第一个节点（主节点）启动命令： galera_new_cluster
后续几个节点数据库服务启动命令就直接用：systemctl start mariadb
查看节点数量：show status like ‘%wsrep_cluster_size%‘;
WSREP: gcs/src/gcs_core.cpp:gcs_core_open():220: Failed to open backend connection: -110
原文：https://www.cnblogs.com/zhongjicainiao/p/12522764.html