[Lustre-discuss] Upgrading From Lustre 1.4 to 1.8

[Kevin Van Maren]

Brian J. Murrell wrote:
> On Thu, 2010-06-10 at 16:04 -0400, Adam wrote: 
>   
>> Hello,
>>     
>
> Hi,
>
>   
>> Would lustre 1.8 be able to work with an LFS created by 1.4?
>>     
>
> As 1.4 has been EOL for nearly (if not more) 2 years now, we have done
> no interoperability testing between 1.4 and 1.8.  I would be very
> surprised if they do inter-operate.
>   

Actually it was June 2009 -- barely one year ago.  It is Lustre 1.6 that 
is being driven to EOL
very quickly -- scheduled for this month.

I believe the older Lustre 1.6 manual covered the necessary migration 
steps from 1.4 -- it was NOT as
painless as moving from 1.6 to 1.8.  The process might also be in the 
mail archives.


>> The 1.8 
>> rolling upgrade strategy discussed on the Lustre wiki is wonderful ( 
>> http://wiki.lustre.org/index.php/Upgrading_to_a_New_Version_of_Lustre#Performing_a_Rolling_Upgrade), 
>>     
>
> Yes, it is.  :-)
>
>   
>> but it only mentions compatibility with 1.6;
>>     
>
> That's right, because that's the extent of the testing we have done with
> it.
>
>   
>> I'm curious if it 
>> would/should also work with an older version of Lustre like 1.4.
>>     
>
> Yes, a rolling upgrade from (perhaps only later versions of) 1.4 to 1.6
> should work and then a rolling upgrade from 1.6 to 1.8.
>
> I would consider trying to upgrade from 1.4 to 1.8 a very risky, and
> likely-to-fail, proposition.
>
> b.
>
>