multipath-tools lacks the default settings for IBM 2810XIV storage system

[bugproxy]

[Impact]
This impacts users of the IBM XIV storage system, which will not function properly with multipath in some circumstances given the missing default settings.

[Test case]
1) Run 'multipath -l';
2) Observe the line immediately below the device header; it should read similar to this:
size=32G features='1 queue_if_no_path' hwhandler='0' wp=rw

As opposed to without the patch:
size=32G features='0' hwhandler='0' wp=rw

Alternatively:
"If a multipath device is configured with features "1 queue_if_no_path", then any process that issues I/O will hang until one or more paths are restored."
1) Remove all paths for a disk drive.
2) Try to list files on the device.

[Regression Potential]
Given that this changes the default settings for the IBM 2810XIV storage systems, if some users of this hardware have come to rely on the incorrect settings provided, the behavior will change.

---Problem Description---
multipath-tools is lacking the settings for IBM 2810XIV storage system

Specially, the lack of queue_if_no_path is problematic on PowerVM LPM (live partition migration) operations,
because I/O errors will trigger filesystem errors, which on ext4 remount the fs in read-only mode, by default.

Please incorporate this upstream commit in 15.10, 15.04 and 14.04:
    864162b08067d3e55d52996846d10a046956c6d6 Add default values for IBM XIV Storage System.

---uname output---
Ubuntu 15.10, 15.04, and 14.04

---Additional Hardware Info---
IBM 2810XIV Storage

The upstream commit applies cleanly on 15.10 (0.5.0-based) and 15.04, 14.04 (0.4.9-based).

[Mauricio Faria de Oliveira (mfo)]

@taco-screen-team

This one probably should be assigned to mathieu-tl, who's been working on multipath-related bugs.

Thanks

[Mauricio Faria de Oliveira (mfo)]

@mathieu-tl

Hi Mathieu, can you add this one to your list, please? Thanks!

[bugproxy (bugproxy)]

------- Comment From <email address hidden> 2015-10-07 11:30 EDT-------
Lowering priority.
We're already customizing multipath.conf anyway, and this shouldn't get in the way of other, more serious ship bugs for Canonical.

[Mathieu Trudel-Lapierre (cyphermox)]

This is a trivial change which is a prime target for a SRU, or if there's another upload of multipath-tools prior to release.

[Mathieu Trudel-Lapierre (cyphermox)]

Is this change really needed on 15.10? It seems to me like we're already carrying the proper options for 2810XIV given that the only elements missing from the hw table are setting configuration options to their default values anyway?

[Mauricio Faria de Oliveira (mfo)]

@mathieu-tl

I think so; afaik queue_if_no_path is not enabled by default.

[Mathieu Trudel-Lapierre (cyphermox)]

This is already in 0.5.0; closing as Fix Released for Wily and Xenial.

[Brian Murray (brian-murray)]

Hello bugproxy, or anyone else affected,

Accepted multipath-tools into trusty-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/multipath-tools/0.4.9-3ubuntu7.8 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, and change the tag from verification-needed to verification-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

[Mauricio Faria de Oliveira (mfo)]

The snippets for IBM XIV are present in the source.

# head -n1 debian/changelog
multipath-tools (0.4.9-3ubuntu7.8) trusty; urgency=medium

# sed -n '/IBM XIV/,/}/ p' libmultipath/hwtable.c
                /* IBM XIV Storage System */
                .vendor = "IBM",
                .product = "2810XIV",
                .getuid = DEFAULT_GETUID,
                .features = "1 queue_if_no_path",
                .hwhandler = DEFAULT_HWHANDLER,
                .selector = DEFAULT_SELECTOR,
                .pgpolicy = MULTIBUS,
                .pgfailback = 15,
                .rr_weight = RR_WEIGHT_NONE,
                .no_path_retry = NO_PATH_RETRY_UNDEF,
                .minio = 15,
                .checker_name = TUR,
                .prio_name = DEFAULT_PRIO,
                .prio_args = NULL,
        },

[Mathieu Trudel-Lapierre (cyphermox)]

Still, it would be important to confirm that they are correctly applied when one such device is attached; for instance, that the right minio values, pgpolicy, etc. are set.

[Brian Murray (brian-murray)]

Hello bugproxy, or anyone else affected,

Accepted multipath-tools into trusty-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/multipath-tools/0.4.9-3ubuntu7.9 in a few hours, and then in the -proposed repository.

Please help us by testing this new package. See https://wiki.ubuntu.com/Testing/EnableProposed for documentation how to enable and use -proposed. Your feedback will aid us getting this update out to other Ubuntu users.

If this package fixes the bug for you, please add a comment to this bug, mentioning the version of the package you tested, and change the tag from verification-needed to verification-done. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed. In either case, details of your testing will help us make a better decision.

Further information regarding the verification process can be found at https://wiki.ubuntu.com/QATeam/PerformingSRUVerification . Thank you in advance!

[Mathieu Trudel-Lapierre (cyphermox)]

This was already verified successfully before; the additional update does not need reverification, only checking the regression in bug 1543430.

[Launchpad Janitor (janitor)]

This bug was fixed in the package multipath-tools - 0.4.9-3ubuntu7.9

---------------
multipath-tools (0.4.9-3ubuntu7.9) trusty; urgency=medium

  * debian/patches/kpartx-support-device-names-with-spaces.patch: fix loopback
    files unmapping. (LP: #1543430)

multipath-tools (0.4.9-3ubuntu7.8) trusty; urgency=medium

  * debian/patches/kpartx-support-device-names-with-spaces.patch: deal with
    spaces in device names in kpartx too (LP: #1432062)
  * debian/initramfs/local-premount: wait for udev to settle before mounting
    so the by-uuid/ symlinks have a chance to be updated by udev rules.
    (LP: #1503286)
  * Allow device detection all through the initramfs: run multipathd instead
    of only scanning once for devices, so those that come up slower can still
    be used as a root device (LP: #1526984):
    - debian/patches/0050-readonly-bindings_prefix.patch,
      debian/patches/0051-readonly-bindings_multipath.patch,
      debian/patches/0052-readonly-bindings_multipathd.patch,
      debian/patches/0053-readonly-bindings_multipathd_prod.patch: support -B
      to allow multipathd to handle cases where the bindings file is read-only.
    - debian/initramfs/hooks: install multipathd and required directories.
    - debian/initramfs/local-premount: also reload all maps to make sure
      they're ready before we mount.
    - debian/initramfs/local-top: run multipathd rather than a one-off call to
      multipath so that new paths can be correctly added as detected while
      we're still in the initramfs.
    - debian/initramfs/local-bottom: remember to stop multipathd.
    - debian/initramfs/local-bottom, debian/rules: install local-bottom for
      initramfs.
  * debian/patches/lp1496210_add_IBM_XIV_defaults.patch: add support (default
    config values) for the IBM 2810XIV storage system. (LP: #1496210)
  * debian/patches/0054-kpartx-update-option.patch: run kpartx -u rather than
    kpartx -a, so as to remove old partition entries if the partition table
    has changed. (LP: #1473903)
  * debian/patches/multipath_enable_sync_support_1b8082c8.patch,
    debian/patches/kpartx_rely_on_udev_dev_creation_9a632fff.patch: synchronize
    udev, device-mapper and multipath, and let udev deal with creating device
    nodes and symlinks. (LP: #1486370)
  * debian/initramfs/local-top: drop scsi_wait_scan stanza, that module is no
    longer available. (LP: #1538775)

 -- Mathieu Trudel-Lapierre <email address hidden> Tue, 09 Feb 2016 16:03:10 -0500

[Adam Conrad (adconrad)]

The verification of the Stable Release Update for multipath-tools has completed successfully and the package has now been released to -updates. Subsequently, the Ubuntu Stable Release Updates Team is being unsubscribed and will not receive messages about this bug report. In the event that you encounter a regression using the package from -updates please report a new bug using ubuntu-bug and tag the bug report regression-update so we can easily find any regressions.