CentOS - Apr 2006 - Pause after network initialization

Is there a "proper" way to put in a pause after network initialization
to
make sure the network *really* is up?  I've had this issue for a while 
with e1000 cards (even on 100MB networks), where the first NFS mount will 
fail b/c the network reports up but isn't, really.  Now, I'm also seeing
the same issue on cluster nodes hooked to a switch with jumbo frames 
enabled.

I used to hack it with a 'sleep 60' at the end of the "start"
function in
/etc/init.d/network, but that goes away whenever initscripts gets updated. 
My new hack is to put 'mount -a -t nfs' in /etc/rc.local.  Any other 
suggestions?

-- 
Joshua Baker-LePain
Department of Biomedical Engineering
Duke University

On Thu, 13 Apr 2006, Joshua Baker-LePain wrote:
> Is there a "proper" way to put in a pause after network 
> initialization to make sure the network *really* is up?  I've had 
> this issue for a while with e1000 cards (even on 100MB networks), 
> where the first NFS mount will fail b/c the network reports up but 
> isn't, really.  Now, I'm also seeing the same issue on cluster
nodes
> hooked to a switch with jumbo frames enabled.
>
> I used to hack it with a 'sleep 60' at the end of the
"start"
> function in /etc/init.d/network, but that goes away whenever 
> initscripts gets updated. My new hack is to put 'mount -a -t nfs'
in
> /etc/rc.local.  Any other suggestions?
If NFS is the only issue, have you considered using the 'bg' mount 
option? The nfs(5) man page discusses it:

   bg    If  the  first  NFS  mount attempt times out, retry the
         mount in the background.  After a  mount  operation  is
         backgrounded,  all  subsequent  mounts  on the same NFS
         server will be backgrounded immediately, without  first
         attempting the mount.  A missing mount point is treated
         as a timeout, to allow for nested NFS mounts.

It's not the default behavior, so you have to specify it in 
/etc/fstab, e.g.,

   server:/export  /mnt/point  nfs  bg,hard,intr  0  0

-- Paul Heinlein <> heinlein at madboa.com <> www.madboa.com