PostgreSQL: Trouble accessing another server's Data via NFS
I figured out the issue. It was due to improperly shared NAS folder. I fixed it by using this entry in /etc/exports

/var/lib/postgresql/ 192.168.1.0/24(rw,nohide,insecure,no_subtree_check,async)


to share.

And if it interests anybody, I managed to get shared database running successfully. The only folder that needed to be common was the above folder. And both PostgreSQL Server instances need to have identical configuration files for the data folder to be shared successfully.