[Bug 1135453] Re: open-iscsi +mpio with multipathd init script order errors

[Ritesh Raj Sarraf]

On Friday 01 March 2013 05:49 PM, Mike Burgener wrote:
> defaults {
>          udev_dir                /dev
>          polling_interval        30
>          selector                "round-robin 0"
>          path_grouping_policy    multibus
>          getuid_callout   "/lib/udev/scsi_id --whitelisted --device=/dev/%n"
>          prio_callout            /bin/true
>          path_checker            readsector0
>          prio                    const
>          rr_min_io               100
>          rr_weight               uniform
>          failback                immediate
>          no_path_retry           12
>          user_friendly_name      yes
>          hardware_handler        "0"
> }

The behavior you reported is pretty interesting. You reported that you
suffered the hang state because the umount occurred after the multipathd
and iscsid processes were killed by the init scripts (which I also
assumed given the new init systems, upstart and systemd).

But looking at your config, you should not typically see the hang
scenario. I was suspecting that you might be using the multipath
queue_if_no_path feature, but that is not the case here. The iscsi
replacement timeouts are also the defaults, i.e. 120 seconds, which
would mean that after 120 seconds of retry, iscsi will error out and the
errors will propagate to the upper layers.

Ideally, with the configuration settings that you have, you should see
the errors show up after 120 seconds, and NOT hang. I have no more ideas
on what might be going wrong in your setup. Perhaps the Ubuntu multipath
maintainer might have some insight to this.

-- 
Ritesh Raj Sarraf
RESEARCHUT - http://www.researchut.com
"Necessity is the mother of invention."

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to multipath-tools in Ubuntu.
https://bugs.launchpad.net/bugs/1135453

Title:
  open-iscsi +mpio with multipathd init script order errors

Status in “multipath-tools” package in Ubuntu:
  New

Bug description:
  when using open-iscsi and multipathd for a mpio setup there are
  several init script logical issues:

  when shutting down, the system does first stop multipathd and then try
  to umount the filesystem and then stop open-iscsi to the system hangs
  forever on shutdown.

  also when booting up it does mount the partition before multipathd and
  open-iscsi are ready and you get the ubuntu screen that the partition
  could not get mounted, do you want to skip.

  after bootup process you can however mount the partition without any
  issue.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/multipath-tools/+bug/1135453/+subscriptions