2010-03-19 20:24:36

by Chuck Lever III

[permalink] [raw]
Subject: Re: unmount -l does not send unmount request to the server

On 03/14/2010 04:40 PM, Guillaume Rousse wrote:
> Le 19/01/2010 17:37, Chuck Lever a =E9crit :
>> As far as I understand it, "-l" means the kernel will do the local
>> detach from the system's file name space whenever there are no more
>> users (ie entirely asynchronously). I don't think umount2(MNT_DETAC=
H)
>> indicates whether the kernel was able to completely unmount that fil=
e
>> system by the time the call returns, so there's perhaps no way for
>> umount.nfs to know whether it should send the UMNT request. If the
>> server is slow or unresponsive, that file system won't be unmounted
>> until long after the umount.nfs command has exited.
>>
>> This shouldn't be much of a big deal, since the server's rmtab is
>> "ornamental" according to the man page. No one should rely on it be=
ing
>> accurate.
>>
>> A possible way to fix this is to have the kernel send the UMNT.
> It makes sense, but it doesn't seem to trigger much interest :)
>
> Should I open a bug somewhere, to ensure the issue won't be forgotten=
?

You might consider filing a bug in the NFSv4 bugzilla on linux-nfs.org.

--=20
chuck[dot]lever[at]oracle[dot]com


2010-03-19 20:57:04

by Trond Myklebust

[permalink] [raw]
Subject: Re: unmount -l does not send unmount request to the server

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