Skip enslaved devices during boot

[Marcelo Cerri]

[Impact]

In some scenarios, we need to skip enslaved network devices from being brought up in initrd.

In order to avoid regressions for other users, the new behaviour is being conditioned to the configuration variable NETWORK_SKIP_ENSLAVED. This mechanism enable us to use it only for the required kernels. The target kernel should be responsible to include the configuration via an initramfs-tools hook.

[Test Case]

Enslaved network devices shouldn't be brought up when the configuration is set by certain kernels. For any other scenario, such as the generic Ubuntu kernel, the behaviour should not be changed.

[Regression Potential]

The potential for regressions was vastly reduced by conditioning the new behaviour.

[Adam Conrad (adconrad)]

Hello Marcelo, or anyone else affected,

Accepted initramfs-tools into cosmic-proposed. The package will build now and be available at https://launchpad.net/ubuntu/+source/initramfs-tools/0.131ubuntu15.1 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 on 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-cosmic to verification-done-cosmic. If it does not fix the bug for you, please add a comment stating that, and change the tag to verification-failed-cosmic. In either case, without details of your testing we will not be able to proceed.

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

N.B. The updated package will be released to -updates after the bug(s) fixed by this package have been verified and the package has been in -proposed for a minimum of 7 days.

[Marcelo Cerri (mhcerri)]

Verification performed in cosmic using the generic kernel (4.18.0-15.16) and the previous behaviour was preserved as expected.

We currently don't have a kernel in cosmic that enables that feature by default, but I built a custom kernel in order to test it and it worked as expected. In theory it was also possible to manually add the config variable, but the test kernel is as closest as we can get to the real use case.

[Launchpad Janitor (janitor)]

This bug was fixed in the package initramfs-tools - 0.131ubuntu15.1

---------------
initramfs-tools (0.131ubuntu15.1) cosmic-security; urgency=medium

  * scripts/functions: include a new option to skip enslaved network
    devices. (LP: #1814818)
      Include the new variable NETWORK_SKIP_ENSLAVED. When set to a
      value different than "0", this variable will cause any enslaved
      network devices to be skipped from the list of netbootable
      devices. This variable can be set via the configuration files
      under /etc/initramfs-tools/ or via any configuration file under
      the initrd directory /conf/conf.d/ via a hook script.

 -- Marcelo Henrique Cerri <email address hidden> Tue, 05 Feb 2019 20:08:09 +0000