Updated mysql-wsrep-5.6.38 requires percona-xtrabackup >= 2.3.5
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<27>Nov 8 19:37:03 node-2 mysqld: 2017-11-08 19:37:03 22086 [Warning] WSREP: Gap in state sequence. Need state transfer.
<27>Nov 8 19:37:03 node-2 mysqld: 2017-11-08 19:37:03 22086 [Note] WSREP: Running: 'wsrep_sst_xtrabackup-v2 --role 'joiner' --address '10.109.1.5' --datadir '/var/lib/mysql/' --defaults -file '/etc/mysql/my.cnf' --defaults-group-suffix '' --parent '22086' '' '
<27>Nov 8 19:37:03 node-2 mysqld: WSREP_SST: [ERROR] FATAL: The innobackupex version is 1.5.1. Needs xtrabackup-2.3.5 or higher to perform SST (20171108 19:37:03.514)
<27>Nov 8 19:37:03 node-2 mysqld: 2017-11-08 19:37:03 22086 [ERROR] WSREP: Failed to read 'ready <addr>' from: wsrep_sst_xtrabackup-v2 --role 'joiner' --address '10.109.1.5' --datadir ' /var/lib/mysql/' --defaults-file '/etc/mysql/my.cnf' --defaults-group-suffix '' --parent '22086' ''
<27>Nov 8 19:37:03 node-2 mysqld: Read: '(null)'
<27>Nov 8 19:37:03 node-2 mysqld: 2017-11-08 19:37:03 22086 [ERROR] WSREP: Process completed with error: wsrep_sst_xtrabackup-v2 --role 'joiner' --address '10.109.1.5' --datadir '/var/l ib/mysql/' --defaults-file '/etc/mysql/my.cnf' --defaults-group-suffix '' --parent '22086' '' : 2 (No such file or directory)
<27>Nov 8 19:37:03 node-2 mysqld: 2017-11-08 19:37:03 22086 [ERROR] WSREP: Failed to prepare for 'xtrabackup-v2' SST. Unrecoverable.
<27>Nov 8 19:37:03 node-2 mysqld: 2017-11-08 19:37:03 22086 [ERROR] Aborting
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Related launhcpad bug: https://bugs.launchpad.net/mos/+bug/1727011
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