[CentOS] boot-time NFS mount failures

[Tilman Schmidt]

Am 19.04.2012 23:10, schrieb Vahan Yerkanian:

>> backup:/home/backup/Oracle      /backup_nfs     nfs
>> hard,intr,noexec,rsize=32768,wsize=32768
> 
> Just add _netdev to the mount options.
> 
>>From man:
> 
> _netdev
> The filesystem resides on a device that requires network access (used to prevent the system from attempting to mount these filesystems until the network has been enabled on the system).

That doesn't seem to have any effect. In fact, I had found
references to that option on the web, but they seemed to
agree that it didn't apply to NFS mounts because CentOS 5
already takes care to do these after the network is up.
To confirm, /etc/init.d/netfs contains the lines

> NFSFSTAB=`LC_ALL=C awk '!/^#/ && $3 ~ /^nfs/ && $3 != "nfsd" && $4 !~ /noauto/ { print $2 }' /etc/fstab`
> SMBFSTAB=`LC_ALL=C awk '!/^#/ && $3 == "smbfs" && $4 !~ /noauto/ { print $2 }' /etc/fstab`
> CIFSFSTAB=`LC_ALL=C awk '!/^#/ && $3 == "cifs" && $4 !~ /noauto/ { print $2 }' /etc/fstab`
> NCPFSTAB=`LC_ALL=C awk '!/^#/ && $3 == "ncpfs" && $4 !~ /noauto/ { print $2 }' /etc/fstab`
> NETDEVFSTAB=`LC_ALL=C awk '!/^#/ && $4 ~/_netdev/ && $4 !~ /noauto/ { print $1 }' /etc/fstab`

for finding the fstab entries to process, and the section
processing NETDEVFSTAB explicitly excludes the fstypes
"nfs,nfs4,smbfs,cifs,ncpfs,gfs" from its mount command.

The netfs service is started after the network service,
so networking on the machine itself is up by that time.
The problem AFAICS is that other servers on the network
which are needed for the mount to succeed (the NFS server
itself and possibly a nameserver) aren't up yet.

Thanks,
Tilman

-- 
Tilman Schmidt
Phoenix Software GmbH
Bonn, Germany