[mythtv-users] Shared filesystem that looks different to different machines

[John Finlay]

On 6/4/2014 10:39 AM, Hika van den Hoven wrote:
> Hoi John,
>
> Wednesday, June 4, 2014, 6:26:17 PM, you wrote:
>
>> On 6/4/2014 8:20 AM, Raymond Wagner wrote:
>>> On 6/4/2014 10:53 AM, Joseph Fry wrote:
>>>> I don't believe that NFS would have any issue with nesting a mount
>>>> inside another mount like this, after all the OS just treats it as
>>>> another filesystem and every linux system I have ever seen does this
>>>> (/dev, /proc, etc).
>>> NFS can have issues if you mount one NFS volume within another NFS
>>> volume.  If access to the lower volume is ever anything but 100%
>>> stable, and the mount point for the upper volume is lost, bad things
>>> happen.  It's the same reason why you never use an NFS share for swap
>>> space.
>> Mounting one NFS filesystem on another NFS filesystem has been commonly
>> used from the beginning of NFS: diskless systems did this all the time.
> True, but if the bottom nfs filesystem gets dirty, which is very
> common if it is accessed by more then one client, you cannot access it
> anymore nor can you remount. You have to reboot.
>
>
>
I'm not sure what you mean by the above but my understanding and 
experience is that NFS was designed to be accessed (i.e. read and write) 
by more than one client and not have problems. If someone removed the 
directory that is being used as the mount point then I can see how that 
would be a problem but otherwise. Also my experience has been that 
mounting NFS filesystems from different servers is a valid configuration 
and works as expected.