[CentOS] NFS help

[Larry Martell]

On Fri, Oct 21, 2016 at 11:42 AM,  <m.roth at 5-cent.us> wrote:
> Larry Martell wrote:
>> On Fri, Oct 21, 2016 at 11:21 AM,  <m.roth at 5-cent.us> wrote:
>>> Larry Martell wrote:
>>>> We have 1 system ruining Centos7 that is the NFS server. There are 50
>>>> external machines that FTP files to this server fairly continuously.
>>>>
>>>> We have another system running Centos6 that mounts the partition the
>>>> files
>>>> are FTP-ed to using NFS.
>>> <snip>
>>> What filesystem?
>>
>> Sorry for being dense, but I am not a sys admin, I am programmer and
>> we have no sys admin. I don't know what you mean by your question. I
>> am NFS mounting to what ever the default filesystem would be on a
>> CentOS6 system.
>
> This *is* a sysadmin issue. Each partition is formatted as a specific type
> of filesystem. The standard Linux filesystems for Upsteam-descended have
> been ext3, then ext4, and now xfs. Tools to manipulate xfs will not work
> with extx, and vice versa.
>
> cat /etc/fstab on the systems, and see what they are. If either is xfs,
> and assuming that the systems are on UPSes, then the fstab which controls
> drive mounting on a system should have, instead of "defaults",
> nobarrier,inode64.

The server is xfs (the client is nfs). The server does have inode64
specified, but not nobarrier.

> Note that the inode64 is relevant if the filesystem is > 2TB.

The file system is 51TB.

> The reason I say this is that we we started rolling out CentOS 7, we tried
> to put one of our user's home directory on one, and it was a disaster.
> 100% repeatedly, untarring a 100M tarfile onto an nfs-mounted drive took
> seven minutes, where before, it had taken 30 seconds. Timed. It took us
> months to discover that NFS 4 tries to make transactions atomic, which is
> fine if you're worrying about losing power or connectivity. If you're on a
> UPS, and hardwired, adding the nobarrier immediately brought it down to 40
> seconds or so.

We are not seeing a performance issue - do you think nobarrier would
help with our lock up issue? I wanted to try it but my client did not
want me to make any changes until we got the bad disk replaced.
Unfortunately that will not happen until Wednesday.