Comment 2 for bug 1531685

This bug was fixed in the package ifupdown - 0.8.6ubuntu1

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ifupdown (0.8.6ubuntu1) xenial; urgency=medium

  * Merge with Debian unstable. Remaining Ubuntu changes:
    - Always call dhclient with -1, Ubuntu carries a patch so that renewal
      won't time out.
    - link.defn, tests/testbuild-linux: Disable upping of bridges as it's not
      covering all the cases supported by the vlan and bridge hooks and so
      causes more harm than good at this point. (LP: #1295304)
    - debian/postinst: Bring back missing /etc/rcS.d/networking symlink, to
      clean up after old broken upgrades. (LP: #1439109) Needs to be kept
      until after 16.04 LTS.
    - ifup@.service, ifupdown-hotplug: Additionally run for "auto" class. We
      don't really support "allow-hotplug" in Ubuntu at the moment, so we need
      to deal with "auto" devices appearing after the "networking" init script
      already ran. (LP: #1374521)
  * Removed Breaks: on udev fixes upgrade failure. (LP: #1531685)

ifupdown (0.8.6) unstable; urgency=medium

  * Remove the Breaks: udev (<< 228-3~) to work around a bug in udev's prerm
    script. Closes: #809658, #809743
  * Run ip link up on manual interfaces, but ignore any errors.
  * Use sysctl to set the IPv6-specific MTU of an interface. Closes: #809714

 -- Martin Pitt <email address hidden> Thu, 07 Jan 2016 11:45:47 +0100