Red Hat 5 ES – NFS down with error: no route to host

Hmm, something happen from last patching on my Red Hat 5 ES servers. Servers were rebooted and one server is using NFS to mount resources and now is getting error message

 ..failed: System error: No Route to host.

Interesting so I have checked my NFS server and run:

 /etc/exports

All seems to be good and shares are configured and good to go so I have tried manually to mount the shared resources and getting this:

     root@server1:mount -t nfs 10.0.2.15:/data/tools/ /data/tools
     mount: mount to NFS server '10.0.2.15' failed: System Error: No Route to host.

Wow, that sucks. So I have researched how to fix it and there are apparently two fixes. Only one worked for me 🙂

  1. Edit /etc/init.d/netfs and add more time like 60 seconds delay before nfs mount shares
  2. Temporary clear iptables rules on the server and – this really worked for me and works for the time of being till new and better solutions can be found
     # /sbin/iptables -L -n (shows what iptables are setup on the machine)
     # /etc/init.d/iptables save
     # /etc/init.d/iptables stop

Once you run the commands and iptables rules were cleared, I have remounted the shares with nfs without problem and all is now working.

. .

QUICK UPDATE: I have just upgraded my Red Hat ES 5.5 server to newest kernel 2.6.18-308.8.2.el5 and updated system and this NFS problem is now resolved 🙂