mounted NFS blocks "forever"

Following next steps my mountd NFS partition blocks "forever":

1.- I start the server NFS process.
2.- I mount the NFS partition like:
mount -t nfs 192.168.2.1:/export/home /home
3.- I stop and start the NFS server, simulating a server/network
temporal shutdown.
4.- The mounted partition doesn't work anymore and simple comands
like:

# ls /home

blocks until I "kill-9" them and there is no way to unmount the device
since trying to unmount it returns "device bussy".

Using ps I see for example that ls is stuck in the kernel call to
nfs_wait_schedule:
[root@/]# ps x -o cmd,wchan | grep ls

ls --color=tty /home nfs_wait_schedule

It's there anyway to avoid such behaviour. I would like, in the worst
case when the NFS servers goes down, to be able to unmount and
remount again.

Thanks in advance for any help,hint or link!


P.S.: I'm using kernel 2.6.20-1.2944.fc6

ENRIQUE wrote:
> 4.- The mounted partition doesn't work anymore and simple comands
> like:
>
> # ls /home
>
> blocks until I "kill-9" them and there is no way to unmount the device
> since trying to unmount it returns "device bussy".

Look at the 'intr' and 'hard' mount options for NFS. (You should probably
set this up in your /etc/fstab file so you don't have to type them every
time you mount the partition.)

--
Steve Wampler -- (E-Mail Removed)
The gods that smiled on your birth are now laughing out loud.

ENRIQUE <(E-Mail Removed)> writes:

> Following next steps my mountd NFS partition blocks "forever":
>
> 1.- I start the server NFS process.
> 2.- I mount the NFS partition like:
> mount -t nfs 192.168.2.1:/export/home /home
> 3.- I stop and start the NFS server, simulating a server/network
> temporal shutdown.
> 4.- The mounted partition doesn't work anymore and simple comands
> like:
>
> # ls /home
>
> blocks until I "kill-9" them and there is no way to unmount the device
> since trying to unmount it returns "device bussy".

I'm puzzled as to why it isn't coming back after the server comes back
up.

> It's there anyway to avoid such behaviour. I would like, in the worst
> case when the NFS servers goes down, to be able to unmount and
> remount again.

The 'soft' option to mount allows HFS to timeout.

ENRIQUE <(E-Mail Removed)> writes:

>Following next steps my mountd NFS partition blocks "forever":

>1.- I start the server NFS process.
>2.- I mount the NFS partition like:
> mount -t nfs 192.168.2.1:/export/home /home
>3.- I stop and start the NFS server, simulating a server/network
>temporal shutdown.
>4.- The mounted partition doesn't work anymore and simple comands
>like:

> # ls /home

>blocks until I "kill-9" them and there is no way to unmount the device
>since trying to unmount it returns "device bussy".

>Using ps I see for example that ls is stuck in the kernel call to
>nfs_wait_schedule:
>[root@/]# ps x -o cmd,wchan | grep ls

>ls --color=tty /home nfs_wait_schedule

>It's there anyway to avoid such behaviour. I would like, in the worst
>case when the NFS servers goes down, to be able to unmount and
>remount again.

Try just mounting again, without trying to unmount.


>Thanks in advance for any help,hint or link!


>P.S.: I'm using kernel 2.6.20-1.2944.fc6