[lustre-devel] llmount.sh does not use fs-specific paths to the ost(s) and mds it mounts

[Quentin BOUGET]

Le 11/05/2016 17:58, James Simmons a écrit :
>> Le 11/05/2016 03:17, Drokin, Oleg a écrit :
>>> On May 10, 2016, at 3:42 PM, Dilger, Andreas wrote:
>>>
>>>> On 2016/05/10, 08:14, "Quentin BOUGET" <quentin.bouget.ocre at cea.fr> wrote:
>>>>> Hello!
>>>>>
>>>>> While trying to mount two different lustre filesystems on a local node
>>>>> with the "llmount.sh" script, I noticed that the path to mount mds and
>>>>> ost(s) was computed like this:
>>>>>
>>>>> eval mntpt=${!var:-${MOUNT%/*}/$facet} # var is not defined by default,
>>>>> so this removes
>>>>>                                                                      #
>>>>> everything after the last '/' of $MOUNT
>>>>>
>>>>>
>>>>> The code can be found at test-framework.sh in the function "facet_mntpt"
>>>>> around the line 3226.
>>>>>
>>>>>
>>>>> By default MOUNT is initialized like this:
>>>>>
>>>>> MOUNT=${MOUNT:-/mnt/${FSNAME}} # default: "/mnt/lustre"
>>>>>
>>>>>
>>>>> Thus the default mountpoints for mds and ost(s) are "/mnt/mds1" and
>>>>> "/mnt/ost1".
>>>>> Because of that, when trying to do two successive calls to "llmount.sh"
>>>>> with two different values for FSNAME, the second fs to be mounted will
>>>>> unmount the first's mds and ost(s) (paths are identical).
>>>>>
>>>>>
>>>>> Is there any reason to truncate the MOUNT variable like this ? Shouldn't
>>>>> the mountpoint path look more like "/mnt/<fsname>-mds1" and
>>>>> "/mnt/<fsname>-ost1"?
>>>> I don't think there is any particular reason it was implemented this way,
>>>> just that it has worked for many years without the need to include the
>>>> fsname into the MDT/OST mount points... :-)
>>>>
>>>> If you want to expand it to allow exporting multiple filesystems from the
>>>> same MDS/OSS nodes then your suggestion to use $FSNAME-$facet in
>>>> facet_mntpt() is reasonable.  Please submit a patch to verify this is
>>>> working correctly.  There may be some places in the tests that aren't
>>>> using facet_mntpt() yet.
>>> I guess to expand on this, since llmount.sh is primarily a testing
>>> infrastructure and typically only one filesystem at a time is tested,
>>> the more than one mountpoint was never bothering anyone till you
>>> discovered this bit, I guess.
>>>
>>> Bye,
>>>       Oleg
>>>
>>>
>> Ok, thank you. I will submit a patch about it.
> Please post a link to the JIRA ticket here. Thanks for the work.
>   
>> Bye,
>>      Quentin
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Here is a link to the JIRA ticket:
https://jira.hpdd.intel.com/browse/LU-8132