on Galera Master-Master sysnced cluster with 2 Nodes, loaded with 2G data and  with set sst_method mariabackup
1. Load 10G data on Node1 
2. Check that data is replicated on Node 2
3. Stop mysql on Node 2
4. Start mysql on Node 2
5. Stop mysql on Node 2
6. Drop small DB on Node 1
7. Start mysql on Node 2
8.  Unexpectedly mysqld failed to start 
Here it occurred the follow:
--instead of IST galera initiated SST 
all data was dropped on Node 2 and was started SST,
SST however failed.
-- stop mysql on  Node 2
-- change sst_method to rsync
-- start mysql on  Node 2 ; mysql failed again
-- return sst_method to mariabackup 
-- start again mysql on  Node 2 :  service mysql start --wsrep_cluster_address=gcomm://192.168.104.196
this time galera initiated --wsrep_recover : /usr/sbin/mysqld --user=mysql --wsrep_recover --disable-log-error
few after mysqld crashed 
mysql    26364 27.0  0.0      0     0 ?        Zl   13:20   0:00 [mysqld] <defunct>