garb open file(./gvwstate.dat.tmp) failed(Permission denied)

when a node restarted its service, belwo warning message will appear

2015-05-19 12:35:28.097 WARN: open file(./gvwstate.dat.tmp) failed(Permission denied)

$ ls -l /gvwstate.dat
-rw-r--r-- 1 root root 265 Mei 13 06:31 /gvwstate.dat

It is safe to ignore?

percona-xtradb-cluster-galera-3.x
Version: 3.9.3494.trusty

The gvwstate.dat should be owned by the same user as the one of mysqld, so usually mysql. Not sure why your file is owned by root, but it will mean the pc.recovery function will not work until mysqld is able to write to this file.
http://galeracluster.com/documentation-webpages/galeraparameters.html#pc-recovery

Just add

GALERA_OPTIONS="base_dir=/var/lib/galera"

to /etc/default/garbd and restart garbd.

I found it here, and it works for me.