Quote Originally Posted by jmozdzen View Post
Hm, sounds strange indeed. My first guess would have been a name resolution issue - but you mentioned that you had tried mounts via IP already.
For those hitting this thread via search:

The issue was resolved, the root cause was a duplicate server IP on the network, which is why it intermittently failed. The "rpcinfo" and tcpdump trace mentioned in elsewhere in this tread was the reply from the wrongly configured machine, which didn't run an NFS server.

Murphy says: If you're hunting down "intermittent" network errors like these, make sure to pay attention to the MAC address of the replying machine. If you're sure the (in this case) server has the service running, but the client will not see it in the server's reply, it is indeed likely that the reply isn't from the server in question

Regards,
J