[Bi-users] Bi login node reboots today at 17-18 CEST

[Kent Engström]

Dear Bi Users,

sorry for the short notice, but... there is a security patch we want to
install on Bi compute nodes and login nodes today. After talking to
our user reps Anders Höglund and Ulf Hansson, we have scheduled a reboot
of the login nodes for today 17-18 CEST.

We will also start a rolling node upgrade as usual (that is, nodes will
be rebooted/updated as jobs finish, so it should not affect any running
jobs).

Note: yesterday we tried a Red Hat-recommended mitigation for the issue,
that turned out to be rather broken. It turns out that it limited stack
size to 30M on the compute nodes at all times (not only in the case
where this matters), causing errors like segmentation violation for
programs allocating more stack space. Some of you may have had jobs
affected by this between ~ 11:00 and 18:30 CEST yesterday (perhaps with
lingering effects for jobs started then and still running). Jobs started
after 18:30 yesterday should not be affected.


Best Regards,
-- 
Kent Engström, National Supercomputer Centre
kent at nsc.liu.se, +46 13 28 4444