group.of.nepali.translators team mailing list archive

[Scott Moser <smoser@xxxxxxxxxx>]

This is fixed in cloud-init 0.7.9.

** Changed in: cloud-init
       Status: Fix Committed => Fix Released

-- 
You received this bug notification because you are a member of नेपाली
भाषा समायोजकहरुको समूह, which is subscribed to Xenial.
Matching subscriptions: Ubuntu 16.04 Bugs
https://bugs.launchpad.net/bugs/1626243

Title:
  Cloud-init fails to write ext4 filesystem to Azure Ephemeral Drive

Status in cloud-init:
  Fix Released
Status in cloud-init package in Ubuntu:
  Fix Released
Status in cloud-init source package in Xenial:
  Fix Released
Status in cloud-init source package in Yakkety:
  Fix Released
Status in cloud-init source package in Zesty:
  Fix Released

Bug description:
  === Begin SRU Template ===
  [Impact]
  There is a race condition that occurs when cloud-init tries to partition a
  block device (/dev/sdb) and then put a filesystem on a partition on it.  It is
  possible that cloud-init tries to run mkfs on /dev/sdb1 after partitioning the
  device /dev/sdb but before the partition device node '/dev/sdb1' exists.

  When this race condition occurs, cloud-init will fail to make the "ephemeral"
  device available to the user on Azure.

  [Test Case]
  A reliable reproduce test case is hard to come by here.  The failure case
  is believed to be well understood.

  [Regression Potential]
  There should be very little chance for regression, as essentially all the change
  does is change:

  1.   sgdisk -n 1:0:0 /dev/sdb
  2.   mkfs.ext4 /dev/sdb1

  to

  1.   sgdisk -n 1:0:0 /dev/sdb
  1a   udevadm settle
  1b   blockdev --rereadpt
  1c   udevadm settle
  2.   mkfs.ext4 /dev/sdb1

  The steps '1b' and '1c' above are not necessary, but were present already in
  the method.  They serve here as additional wait.

  [Other Info]
  The change that fixes this is viewable at [1].  For context, viewin all of
  cc_disk_setup.py [2].  Basically we just add a call to read_parttbl [3] to
  exec_mkpart_gpt after invoking a sgdisk command that partitions a disk.
  read_partbl basically does a udevadm settle which fixes the race condition that
  was seen.

  [1] https://git.launchpad.net/cloud-init/commit/?id=29348af1c889931e8973f8fc8cb090c063316f7a
  [2] https://git.launchpad.net/cloud-init/tree/cloudinit/config/cc_disk_setup.py?id=29348af1c889931e8973f8fc8cb090c063316f7a
  [3] https://git.launchpad.net/cloud-init/tree/cloudinit/config/cc_disk_setup.py?id=29348af1c889931e8973f8fc8cb090c063316f7a#n674

  === End SRU Template ===

  The symptom is similar to bug 1611074 but the cause is different. In
  this case it seems there is an error accessing /dev/sdb1 when lsblk is
  run, possibly because sgdisk isn't done creating the partition. The
  specific error message is "/dev/sdb1: not a block device." A simple
  wait and retry here may resolve the issue.

  util.py[DEBUG]: Running command ['/sbin/sgdisk', '-p', '/dev/sdb'] with allowed return codes [0] (shell=False, capture=True)
  cc_disk_setup.py[DEBUG]: Device partitioning layout matches
  util.py[DEBUG]: Creating partition on /dev/disk/cloud/azure_resource took 0.056 seconds
  cc_disk_setup.py[DEBUG]: setting up filesystems: [{'filesystem': 'ext4', 'device': 'ephemeral0.1', 'replace_fs': 'ntfs'}]
  cc_disk_setup.py[DEBUG]: ephemeral0.1 is mapped to disk=/dev/disk/cloud/azure_resource part=1
  cc_disk_setup.py[DEBUG]: Creating new filesystem.
  cc_disk_setup.py[DEBUG]: Checking /dev/sdb against default devices
  cc_disk_setup.py[DEBUG]: Manual request of partition 1 for /dev/sdb1
  cc_disk_setup.py[DEBUG]: Checking device /dev/sdb1
  util.py[DEBUG]: Running command ['/sbin/blkid', '-c', '/dev/null', '/dev/sdb1'] with allowed return codes [0, 2] (shell=False, capture=True)
  cc_disk_setup.py[DEBUG]: Device /dev/sdb1 has None None
  cc_disk_setup.py[DEBUG]: Device /dev/sdb1 is cleared for formating
  cc_disk_setup.py[DEBUG]: File system None will be created on /dev/sdb1
  util.py[DEBUG]: Running command ['/bin/lsblk', '--pairs', '--output', 'NAME,TYPE,FSTYPE,LABEL', '/dev/sdb1', '--nodeps'] with allowed return codes [0] (shell=False, capture=True)
  util.py[DEBUG]: Creating fs for /dev/disk/cloud/azure_resource took 0.008 seconds
  util.py[WARNING]: Failed during filesystem operation#012Failed during disk check for /dev/sdb1#012Unexpected error while running command.#012Command: ['/bin/lsblk', '--pairs', '--output', 'NAME,TYPE,FSTYPE,LABEL', '/dev/sdb1', '--nodeps']#012Exit code: 32#012Reason: -#012Stdout: ''#012Stderr: 'lsblk: /dev/sdb1: not a block device\n'

To manage notifications about this bug go to:
https://bugs.launchpad.net/cloud-init/+bug/1626243/+subscriptions