As the next step in our storage redundancy and reliability efforts for Labs, we have a significant migration coming up on 11/2 starting 08:00 PST(15:00 UTC) involving the tools NFS share. The maintenance window can be up to 48h long, and will affect most running tools. At the end of the migration, everything (except transient jobs) should ideally be working the same way as they were before the migration, but better.

Here's what to expect during the maintenance window:

    

* The tools NFS share (/data/project and /home) will be read-only for the duration of the maintenance, so no new data or logs will get written to it.

* New jobs cannot be submitted for the whole maintenance window - this means submitting jobs through cron or tools-mail will not function, although tools-mail can continue to send emails. 

* Current jobs might keep running, but won't get rescheduled if they die. If they do not die and aren't writing to NFS they should be fine. 

* All exec nodes will get depooled, rebooted and repooled and jobs that don't get rescheduled automatically will have died and need manual restarts.

Do let us know if you have any questions or concerns on the lists or on #wikimedia-labs.

Madhumitha Viswanathan

Operations Engineer, Wikimedia Labs