Galera recovery process works in two phases. In the first
phase, mysqld is started as non-daemon with --wsrep-recover
to recover and fetch the last logged global transaction ID.
This ID is then used in second phase as the start position
(--wsrep-start-position=XX) to start mysqld as daemon.
As this process was implemented in mysqld_safe script, the
recovery did not work when server was started using systemd.
Fixed by introducing a shell script (wsrep_recovery.sh) that
mimics the first phase of the recovery process.