[Lustre-discuss] NFS Export Issues

[William Olson]

On 7/16/2010 6:16 PM, Kevin Van Maren wrote:
> But the client is doing a lstat on /mnt/lustre_mail_fs, not 
> /mnt/lustre -- what is the mount command again?
>

I think my server names are confusing the situation..

Lustre client = NFS server
Lustre is mounted in /mnt/lustre_mail_fs
/mnt/lustre_mail_fs is exported with NFS

NFS client is attempting to mount the /mnt/lustre_mail_fs export to it's 
/mnt/lustre directory..

mountd(on the NFSserver/lustre client) fails to stat the correctly 
mounted and fully operational /mnt/lustre_mail_fs, during an NFS client 
connection attempt.
The NFS client authenticates properly according to the logs, it's only 
when mountd attempts to stat the lustre fs that problems arise..

Again, for clarity, I can successfully export and mount any other 
directory from this same machine, to the same client..

> On Jul 16, 2010, at 6:50 PM, William Olson <lustre_admin at reachone.com> 
> wrote:
>
>> On 7/16/2010 5:41 PM, Kevin Van Maren wrote:
>>> Looks like a problem with your mount point.  What are the 
>>> permissions on the client directory?
>>>
>> NFSServer/Lustre Client
>>
>> Lustre mounted:
>> drwxrwxrwx 29 root root 4.0K Jul 12 17:03 lustre_mail_fs
>> Lustre not mounted:
>> drwxrwxrwx 2 root root 4.0K Jun 10 13:26 lustre_mail_fs
>>
>> NFSClient mount dir:
>> drwxrwxrwx  2 root root 4.0K Jul 12 15:09 lustre
>>
>>>
>>> On Jul 16, 2010, at 6:23 PM, William Olson 
>>> <lustre_admin at reachone.com> wrote:
>>>
>>>> On 7/16/2010 5:12 PM, Andreas Dilger wrote:
>>>>>
>>>>>> Well that improved the debug level, but didn't reveal any -2 
>>>>>> errors..   In fact I can't seem to find a line with an error in 
>>>>>> it... Is there a specific verbiage used on error lines that I can 
>>>>>> grep for?  90% is "Process entered" or "Process leaving"...
>>>>>>
>>>>> You could try "strace -f" on the mount process, to see which 
>>>>> syscall is failing.  It may be failing with something before it 
>>>>> gets to Lustre.
>>>>>
>>>> Results of strace below:
>>>>
>>>> [root at lustreclient mnt]# strace -f -p 15964
>>>> Process 15964 attached - interrupt to quit
>>>
>>>
>>>
>>>> lstat("/mnt", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
>>>> lstat("/mnt/lustre_mail_fs", 0x7fff4bd4b2b0) = -1 EACCES 
>>>> (Permission denied)
>>>> stat("/etc/localtime", {st_mode=S_IFREG|0644, st_size=2875, ...}) = 0
>>>
>>>
>>