Re: Killing process in D state on mount to dead NFS server.

[Ben Greear <greearb@candelatech.com>]

On 07/31/2014 12:49 PM, Malahal Naineni wrote:
> Ben Greear [greearb@candelatech.com] wrote:
>> So, this has been asked all over the interweb for years and years, but
>> the best answer I can find is to reboot the system or create a fake NFS
>> server somewhere with the same IP as the gone-away NFS server.
>>
>> The problem is:
>>
>> I have some mounts to an NFS server that no longer exists (crashed/powered down).
>>
>> I have some processes stuck trying to write to files open on these mounts.
>>
>> I want to kill the process and unmount.
>>
>> umount -l will make the mount go a way, sort of.  But process is still hung.
>> umount -f complains:
>>   umount2:  Device or resource busy
>>   umount.nfs: /mnt/foo: device is busy
>>
>> kill -9 does not work on process.
>>
>>
>> Aside from bringing a fake NFS server back up on the same IP, is there any
>> other way to get these mounts unmounted and the processes killed without
>> rebooting?
> 
> You don't need a fake NFS server, you just need a fake or real server
> with that IP address.  A popular way is to alias that IP on the NFS
> client itself.
> 
> See the second popular answer below:
> http://stackoverflow.com/questions/40317/force-unmount-of-nfs-mounted-directory

In my case, routing is set up so that the NFS traffic always exits the system, so
doing a local IP that matches the server is not an option.  It also seems like a
horrible hack that should have a better solution :P

Thanks,
Ben

> 
> Regards, Malahal.


-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com