>Subject: Re: NFS failover info..
>Date: 1/26/04 10:41 AM Hawaiian Standard Time
>>Subject: Re: NFS failover info..
>>Date: 1/26/04 7:28 AM Hawaiian Standard Time
>>> Hi folks,
>>> I was wondering how NFS failover works in practice. I have two servers
>>> each shared file system, with the shared files being identical on the
>>> The automount maps also reflect that there are two servers.
>>> So if one server fails, how quickly will the nfs clients respond, and
>>> from the alternative server? And should things run smoothly after that, or
>>> their anything else that needs to be done?
>>This only works with read-only mounts.
>>And even so, it's not very popular. I've seen a few posts from admins
>>asking about it and not being able to see the failover occur.
>Yeah thats what I was wondering. I had my suspicions about that working well
>an actual operating environment.
Ok, I did the following basic experiment which was suggested earlier.
I made an old version of blt I had laying around exportable read only from two
machines. The directory /export/blt2.4 is absolutely identical on both
I then mounted that partition on a client:
mount -o ro host1,host2:/export/blt2.4 /blt
host1 is running 2.7. host2 running 2.9 and the client running 2.8. Not ideal,
I know, but if it works like that, its at least somewhat robust. Now I'm pretty
share failover capability was introduced in 2.6. If it was introduced after
2.7, then obviously, this is a bad experiment.
After issuing the mount command I cd'ed into /blt on the client. I then
determined it was mounting from host1. So I unshared /export/blt2.4 on host1.
When trying to do an ls on the client, it responded "Stale NFS Handle". Cd'ing
in and out didn't help.
THere was no failover as I understand "failover" to mean.
SO much for that, I guess.
Dr. Stuart A. Weinstein
Ewa Beach Institute of Tectonics
"To err is human, but to really foul things up
requires a creationist"