Server Fault is a question and answer site for system and network administrators. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

I've had some hard time configuring NFS4 with Kerberos last time. Finally I made it but there are few things I do not fully understand yet. One of them is: why DNS resolution of hostnames is not enough?

I have 2 machines: nfsserver, nfsclient.

Both are resolvable through local DNS, so I can e.g. ping nfsserver from nfsclient by hostname or FQDN and vice versa.

Now I can not mount nfsserver's export until I add its record into /etc/hosts on nfsclient. It freezes on:

mount.nfs4: trying text-based options 'sec=krb5p,addr=,clientaddr='

In /etc/nsswitch.conf I have:

hosts:          files dns

What is the reason/mechanism behind it?

share|improve this question
up vote 1 down vote accepted

Ping is not the most appropriate tool to debug DNS trouble. Indeed, ping does not perform any reverse resolution to check if direct and reverse resolutions match (the purpose is only to send an ICMP packet to the IP address directly resolved from the FQDN parameter).

If I were you, I would ensure with host or dig command if direct resolution (host my_fqdn_server should return my_server_IP - This part looks like OK) and the reverse resolution (host my_server_IP should return my_fqdn_server) should return the same.

Anyway, I would guess your DNS server (which one are you using? And do you have access on its configuration?) is misconfigured.

share|improve this answer
The reason was indeed a lack of revdns entry for nfsserver in my local DNS. Thanks! :) – Mike Apr 30 '13 at 10:02

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.