超时导致的Galera节点加入集群失败
需求：为galera集群添加新的节点。
初始化新的节点，加入的时候一直报错，加入失败，报错日志如下
1 WSREP_SST: [ERROR] Removing /var/lib/mysql//.sst/xtrabackup_galera_info file due to signal (20180420 19:06:51.356) 2 WSREP_SST: [ERROR] Cleanup after exit with status:143 (20180420 19:06:51.360) 3 2018-04-20 19:06:51 139809385338624 [ERROR] WSREP: Process completed with error: wsrep_sst_xtrabackup-v2 --role 'joiner' --address '172.20.3.11' --datadir '/var/lib/mysql/' --parent '149146' --binlog '/var/lib/mysql/mysql-bin' : 4 (Interrupted system call) 4 2018-04-20 19:06:51 139809385338624 [ERROR] WSREP: Failed to read uuid:seqno and wsrep_gtid_domain_id from joiner script. 5 2018-04-20 19:06:51 139809916561536 [ERROR] WSREP: SST failed: 4 (Interrupted system call) 6 2018-04-20 19:06:51 139809916561536 [ERROR] Aborting
最后怀疑是由于数据库较大，在同步过程中导致数据库超时报错，解决方法如下：
vim /usr/lib/systemd/system/mariadb.service
[Service]
TimeoutSec=2h
重启mysql，节点正常加入。
