Hi all,

Is it possible to force nfs to only use ipaddresses and not rely on dns? 

My main server at home hosts all my dvdrips and music for a MythTV box 
in the livingroom.  Lately Comcast has been having hardware problems, 
and I've lost connections, and today I find that their main dns servers 
are unreachable.  I became aware of it because /usr/bin/exportfs would 
hang when trying to start the nfs server.  After trying to find some 
sort of log or kernel error somewhere and comming up with nothing, I 
checked google for a while (quite difficult with no/intermitent dns) and 
found that if there are any entries in /var/lib/nfs/*tab that exportfs 
can't resolve it will hang.  I removed all the entries from the rmtab 
file, and the rest were already empty, but still no go. 

I remembered the ISC reports on the DNS Poisoning that's been happening 
lately, and used thier public dns servers they posted in the diarys, and 
sure enough exportfs loaded without a problem. 

I have no idea why it worked, but it did.  There were no entries in 
/var/lib/nfs/*tab, that and all the entries that were there were listed 
by ip anyway.  Even the /etc/export file only lists ips.  As far as I 
could tell, everything related to nfs was using ip addresses.  All the 
addresses are private 192.168.0.* so it can't do a reverse lookup.  
Nothing is pointing me to why my nfs server froze waiting for a dns query.

I'm using the public dns servers from ISC (4.2.2.1, 4.2.2.2, 4.2.2.3) 
for the time being until Comcast fixes their hardware issues.  And for a 
failsafe, I've added the MythTV box to /etc/hosts.  But for future 
reference can I somehow disable dns in the nfs server tools?  Or is 
there anything I can do to prevent future Comcast (or other isp) 
problems from spilling over onto me?  I do run a caching nameserver, is 
there some way I can rig it that would allow nfs to work when the main 
dns servers are unreachable?

Thanks all,

Chris Frederick