Re: Cannot unmount nfs4 sec=krb5 mount if network is down

[Orion Poplawski <orion@cora.nwra.com>]

On 05/17/2012 04:29 AM, Karel Zak wrote:
> On Wed, May 16, 2012 at 09:34:27PM +0000, Orion Poplawski wrote:
>> Orion Poplawski<orion@...>  writes:
>>>
>>> See https://bugzilla.redhat.com/show_bug.cgi?id=820707
>>>
>>> If the network is disconnected it is impossible to unmount, even if no
>>> processes are accessing the mount.  umount -f and umount -l both hang on
>>> readlink("/home/orion").
>>
>> umount needs to canonicalize the path so it does a readlink on the path given to
>> it.
>
> It seems that the canonicalization is unnecessary (already fixed in libmount
> upstream code). https://bugzilla.redhat.com/show_bug.cgi?id=820707
>

That appears to fix the issue for me.  Thanks!

>> This appears to wait forever.  This pretty much makes it impossible to use krb5
>> nfs4 with laptops where the network can disappear.
>
> Is it possible to interrupt this "wait" by signal? ... then we can add alarm()
> to critical sections in programs like umount or lsof.
>
> Now for example lsof resolves this problem by fork() and timeout in
> parent.. that's pretty nasty solution :-(
>
>      Karel
>

Seems unnecessary with the above fix.

-- 
Orion Poplawski
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