Power

Hello,

i want to setup my nfs mount on AIX so that if nfs server is not reachable there will be no hang. We setup nfs with soft mount but we notice that if the nfs server is not available during boot time the boot process hangs. 

our nfs mount on /etc/filesystems looks like this:

/nfsmount:

    dev         = "/nfsdir"

    vfs         = nfs

    nodename    = nfsserver

    mount       = true

    options     = bg,soft,intr,timeo=5,retrans=2

    account     = false

anything to rectify ?

Same here, and initially due to NFS mount hangs, but also entries that had an "wait" when they should have a "respawn" or "once".

I usually put the console right after the srcmstr.

This is a well-known problem.  The NFS "mount=true" filesystems are processed in rc.nfs, causing the mounts of offline servers to hang.

A more robust solution is to set all the NFS filesystems with "mount=false" and "type=net", then add an inittab entry after rc.nfs:

nfsmnt:23456789:once:/usr/sbin/mount -t net > /dev/console 2>&1 # Note: it MUST be "once" so that it doesn't hang the rest of the inittab

Another thing: an hung NFS mount directly on the root directory will cause path descent to hang if the server is unavailable.  This will happen for every single command that is exec'ed on the system.

The workaround is to mount in /server/SERVERNAME/mountpoint and set a symbolic link in the previous mount location. 

What I do is temporarily mount my software repo that lives on my NIM server.

mount -o ro,soft,vers=3 nim0X:/softwareRepo /mnt

The problem we had was that when we rebooted the nim server, the clients would get upset and hang a bit.  So, I have a command that goes out to the Nim clients and unmounts "/mnt" after a period of time.  The Mount command reports the date when file systems have been mounted.  So, what I do is if I mount /mnt in May, it will get unmounted in July.  It will be mounted for at least ~30 days and at most ~60 days.  If we are going to reboot the NIM server, we will scan the systems and unmount /mnt.

# As you can see we see the date when the file system was mounted

# mount |grep mnt
nim0X //softwareRepo /mnt             nfs3   Jul 02 10:18 ro,soft,vers=3

NOTE: Redhat does not report the date.  I also noticed that Azure uses/mnt for storage.  I do not auto-unmount on Linux.

Another alternative is to use the automounter, that way the mounts are only done when you need them.