[Bug 1743249] Re: Failed Deployment after timeout trying to retrieve grub cfg

[Jason Hobbs]

On Mon, Feb 5, 2018 at 11:58 AM, Andres Rodriguez
<andreserl at ubuntu-pe.org> wrote:
> No new data was provided to mark this New in MAAS:
>
> 1. Changes to the storage seem to have improved things

Yes, it has.  That doesn't change whether or not there is a bug in
MAAS.  Can you please address the critical log errors that I mentioned
in comment #36?  This seems like enough to establish something is
going wrong in MAAS.

> 2. No tests have been run with fixed grub that have caused boot
failures.

The comments from #56 were testing with the fixed grub - sorry if that
wasn't clear.

> 3. AFAIK, the VM config has not changed to use less CPU to compare
results and whether this config change causes the bugs in question.

The CPU load data from comments #48 and #50 shows that CPU load is not
the problem.  The max load average was under 12 on a 20 thread system.
That means there was lots of free CPU time, and that this workload is
not CPU bound.

Jason


** Changed in: maas
       Status: Incomplete => New

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to grub2 in Ubuntu.
https://bugs.launchpad.net/bugs/1743249

Title:
  Failed Deployment after timeout trying to retrieve grub cfg

Status in MAAS:
  New
Status in grub2 package in Ubuntu:
  In Progress

Bug description:
  A node failed to deploy after it failed to retrieve a grub.cfg from
  MAAS due to a timeout.  In the logs, it's clear that the server tried
  to retrieve the grub cfg many times, over about 30 seconds:

  http://paste.ubuntu.com/26387256/

  We see the same thing for other hosts around the same time:

  http://paste.ubuntu.com/26387262/

  It seems like MAAS is taking way too long to respond to these
  requests.

  This is very similar to bug 1724677, which was happening pre-
  metldown/spectre. The only difference is we don't see "[critical] TFTP
  back-end failed" in the logs anymore.

  I connected to the console on this system and it had errors about
  timing out retrieving the grub-cfg, then it had an error message along
  the lines of "error not an ip" and then "double free".  After I
  connected but before I could get a screenshot the system rebooted and
  was directed by maas to power off, which it did successfully after
  booting to linux.

  Full logs are available here:
  https://10.245.162.101/artifacts/14a34b5a-9321-4d1a-b2fa-
  ed277a020e7c/cpe_cloud_395/infra-logs.tar

  This is with 2.3.0-6434-gd354690-0ubuntu1~16.04.1.

To manage notifications about this bug go to:
https://bugs.launchpad.net/maas/+bug/1743249/+subscriptions