ifenslave can't delete interfaces from a bond

[Kees Hoekzema]

Deleting an interface from a bond does not work and gives you an error: "$interface is not enslaved to $bond"

To reproduce:

# cat /etc/modprobe.d/bonding.conf
alias bond0 bonding
alias bond1 bonding
options bond0 mode=1 primary=em1 max_bonds=2
options bond1 mode=1 primary=em3 max_bonds=2

# modprobe bond0
# modprobe bond1
# ifenslave bond0 em1 em2
# ifenslave bond1 em3 em4

works (almost) fine, in /proc/net/bonding/bond* everything looks enslaved (but bond1 does not have a primary slave)

However, deleting an interface from a bond results in an error:
# ifenslave -d bond1 em4
em4: is not enslaved to bond1

em4 is still enslaved according to /proc/net/bonding/bond1

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: ifenslave 2.4ubuntu1
ProcVersionSignature: Ubuntu 3.13.0-19.40-generic 3.13.6
Uname: Linux 3.13.0-19-generic x86_64
ApportVersion: 2.13.3-0ubuntu1
Architecture: amd64
Date: Thu Mar 27 12:28:03 2014
InstallationDate: Installed on 2014-03-26 (1 days ago)
InstallationMedia: Ubuntu-Server 13.10 "Saucy Salamander" - Release amd64 (20131016)
PackageArchitecture: all
ProcEnviron:
 LANGUAGE=en_US:en
 TERM=linux
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: ifenslave
UpgradeStatus: Upgraded to trusty on 2014-03-26 (1 days ago)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Kees (kees2014)]

I experience the same issue.

As a workaround this works:
sudo su
echo -p5p5 /sys/class/net/bond1/bonding/slaves

[T Parys (tparys)]

Looks like a bad case of copy / paste. Lines 111-112 appear to be copied from lines 96-97, with the logical checks flipped. Looks like they forgot to swap the Boolean.

Patch attached. Could we get a dev to apply the fix?

[T Parys (tparys)]

Updated tags to include xenial, as bug is still present.

[Ubuntu Foundations Team Bug Bot (crichton)]

The attachment "Patch to ifenslave" seems to be a patch. If it isn't, please remove the "patch" flag from the attachment, remove the "patch" tag, and if you are a member of the ~ubuntu-reviewers, unsubscribe the team.

[This is an automated message performed by a Launchpad user owned by ~brian-murray, for any issues please contact him.]

[Brian Murray (brian-murray)]

It looks like Debian is affected by the same bug, so it'd be worth forwarding the bug and your patch to Debian also. Thanks!

[Launchpad Janitor (janitor)]

This bug was fixed in the package ifenslave - 2.9ubuntu1

---------------
ifenslave (2.9ubuntu1) bionic; urgency=low

  * Merge from Debian unstable. Remaining changes:
    - Upstart event based bond bringup:
      + Drop ethernet+wifi example
      + Drop two_ethernet example
      + Update ethernet+hotplug_wifi example
      + Update two_hotplug_ethernet example
      + Update pre-up and post-down scripts for event bringup
      + Update README.Debian examples
    - Update scripts to use /run/network/ifstate instead of
      /etc/network/run/ifstate

ifenslave (2.9) unstable; urgency=medium

  [ Peter Pentchev ]
  * Brown paper bag: fix the correct check for detaching interfaces,
    this time really closing #838918 and unbreaking attachment, too.

ifenslave (2.8) unstable; urgency=medium

  [ Peter Pentchev ]
  * Fix detaching interfaces after the /slave_ to /lower_ change
    (Closes: #838918, LP: #1298325).
  * Declare compliance with version 3.9.8 of the Debian Policy Manual.
  * Fix some typographical and grammatical errors.
  * Switch to the HTTPS scheme for the VCS and copyright format URLs.
  * Switch to cgit for the Vcs-Browser field.
  * Bump the debhelper compatibility version to 10 with no changes.
  * Stop suggesting that bugs be filed against ifenslave-2.6 when
    the package name is ifenslave now.

 -- Steve Langasek <email address hidden> Fri, 16 Mar 2018 16:04:23 -0700

[Tilman Baumann (tilmanbaumann)]

Can we have that in Xenial as well?