[Beowulf] Lustre Upgrades

[Paul Edmon]

We have some old large scale Lustre installs that are running 2.6.34 and 
we want to get these up to the latest version of Lustre.  I was curious 
if people in this group have any experience with doing this and if they 
could share them.  How do you handle upgrades like this?  How much time 
does it take?  What are the pitfalls?  How do you manage it with minimal 
customer interruption? Should we just write off upgrading and stand up 
new servers that are on the correct version (in which case we need to 
transfer the several PB's worth of data over to the new system)?

Thanks for your wisdom.

-Paul Edmon-