Lustre discuss - Sep 2012 - Fwd: Lustre Interoperability Question

Hi,

Re-send to the proper (I hope) email list.

Megan

---------- Forwarded message ----------
From: Ms. Megan Larko <dobsonunit at gmail.com>
Date: Wed, Sep 19, 2012 at 4:24 PM
Subject: Lustre Interoperability Question
To: lustre-discuss-request at lists.lustre.org


Hello List!

I am looking for clarification on a Lustre interoperability question.
 There is a system currently running RHEL 5.5 and Lustre 1.8.3 to
which new hardware would like to be added.  The new hardware is not
supported under RHEL 5.x so it needs to be installed as RHEL 6.2 as a
minimum.   There is considerable doubt that one section of the old
hardware will be able to function under RHEL 6.   A version of the
Lustre Manual for 2.0 (
http://wiki.lustre.org/manual/LustreManual20_HTML/UpgradingLustre.html
) Section 16.1 indicates the possibility of heterogenous Luster
servers---specifically mixed 1.8 and 2.0 servers.  Section 16.1 goes
on to state that Lustre 1.8.4 must be on the client and server nodes
not upgraded to 2.0.

Further research on this issue led me to Whamcloud LU-1116 (
http://jira.whamcloud.com/browse/LU-1116 ) in which a bug (actually a
linux kernel item name change) indicates that for a RHEL 6.2 client to
support 1.8 Lustre (and 2.0 Lustre)  the clients minimum Lustre
version must be 1.8.7 (patched) or 1.8.8 (where the patch is landed).

The Question:  Can Lustre effectively serve a file system with
heterogenous servers of RHEL 5.5 (1.8.3) and RHEL 6.2 (2.1 or better)?

If not, would a solution of RHEL 5.5 with an upgrade from 1.8.3 to
1.8.8 function  with the new hardware using RHEL 6.2 (either Lustre
1.8.8 or 2)?   Do the clients have to run Lustre 1.8.8 at a minimum?

All guidance and suggestions are appreciated.

Cheers!
Megan Larko

On 2012-09-19, at 10:38 PM, Ms. Megan Larko wrote:
> I am looking for clarification on a Lustre interoperability question.
> There is a system currently running RHEL 5.5 and Lustre 1.8.3 to
> which new hardware would like to be added.  The new hardware is not
> supported under RHEL 5.x so it needs to be installed as RHEL 6.2 as a
> minimum.   There is considerable doubt that one section of the old
> hardware will be able to function under RHEL 6.   A version of the
> Lustre Manual for 2.0 (
> http://wiki.lustre.org/manual/LustreManual20_HTML/UpgradingLustre.html
> ) Section 16.1 indicates the possibility of heterogenous Luster
> servers---specifically mixed 1.8 and 2.0 servers.  Section 16.1 goes
> on to state that Lustre 1.8.4 must be on the client and server nodes
> not upgraded to 2.0.
> 
> Further research on this issue led me to Whamcloud LU-1116 (
> http://jira.whamcloud.com/browse/LU-1116 ) in which a bug (actually a
> linux kernel item name change) indicates that for a RHEL 6.2 client to
> support 1.8 Lustre (and 2.0 Lustre)  the clients minimum Lustre
> version must be 1.8.7 (patched) or 1.8.8 (where the patch is landed).
> 
> The Question:  Can Lustre effectively serve a file system with
> heterogenous servers of RHEL 5.5 (1.8.3) and RHEL 6.2 (2.1 or better)?
> 
> If not, would a solution of RHEL 5.5 with an upgrade from 1.8.3 to
> 1.8.8 function  with the new hardware using RHEL 6.2 (either Lustre
> 1.8.8 or 2)?   Do the clients have to run Lustre 1.8.8 at a minimum?
Interop rules are:
- servers all need to run the same version of Lustre
- 2.x clients will not work with 1.8 servers
- 1.8.7 clients will work with 2.x servers
- 2.1 clients will work with both RHEL5 and RHEL6

Best would be running 2.1.3 clients and servers everywhere.

Cheers, Andreas
--
Andreas Dilger                       Whamcloud, Inc.
Principal Lustre Engineer            http://www.whamcloud.com/