From this guide we know DRBD can used for PostgreSQL Active/Passive setting:
/dev/drbd0 to mount PostgreSQL data path
mount -t ext3 /dev/drbd0 /var/lib/pgsql
So is it possible to use this way to mount a MongoDB data path and where is that path?（Maybe this on CentOS 7.3:
If use this way, the multiple nodes will use the synced same file data but not master-slave replication. Maybe this is called master-master replication. Is it good?