Changes/RemoveDeviceMapperMultipathFromWorkstationLiveCD

Remove device-mapper-multipath from the Fedora workstation livecd

Summary

The Fedora workstation livecd is the default Fedora variant getfedora.org advices people to download. As such most Fedora workstation installs will be done from the livecd. This means that any package which is part of the livecd will be part of the default install for most users.

device-mapper-multipath is 1 of only 2 packages in the default install which still Requires the long obsoleted systemd-udev-settle.service, which waits for all device-detection to be done + some extra waiting just to be sure. This significantly slows down booting on various systems.

Multipath support is only necessary for installations in data-centers or other enterprise setups, as such having device-mapper-multipath on the livecd is not really necessary. For installations which do actually need this device-mapper-multipath the server installation iso can be used and this is a better fit for such installations.

Owner

• Name: Hans de Goede
• Email: hdegoede@redhat.com

Current status

• Targeted release: Fedora 33
• Last updated: 2020-07-07
• FESCo issue: #2434
• Tracker bug: <will be assigned by the Wrangler>
• Release notes tracker: <will be assigned by the Wrangler>

Detailed Description

device-mapper-multipath is 1 of only 2 packages in the default install which still Requires the long obsoleted systemd-udev-settle.service. The other package is dmraid see Disable dmraid.service on first run.

Multipath support is only necessary for installations in data-centers or other enterprise setups, as such having device-mapper-multipath on the livecd is not really necessary. For installations which do actually need this device-mapper-multipath the server installation iso can be used and this is a better fit for such installations.

Note then when installing from the server or everything netboot isos, device-mapper-multipath depending on the obsolete udev-settle service is not a problem, because then it will not be installed at all. Anaconda (the installer) adds storage related packages such as device-mapper-multipath to the installation package-set as necessary for the storage found at installation time. So any installs done through the netinst isos already will not have device-mapper-multipath installed.

Benefit to Fedora

systemd-udev-settle.service causes a significant and sometimes quite long delay during boot. Removing / disabling the last 2 services depending on this long obsolete helper service will remove the unnecessary boot delay.

Scope

• Proposal owners:
  • Change the livecd packagelist (comps) to no longer include the device-mapper-multipath package

• Other developers:
  • No action is required by other developers
  • Except if another package still brings in device-mapper-multipath through dependencies, then this needs to be solved / coordinated with that other packages maintainers

• Release engineering: #9560 (a check of an impact with Release Engineering is needed)

• Policies and guidelines: N/A (not needed for this Change)

• Trademark approval: N/A (not needed for this Change)

Upgrade/compatibility impact

This only affects new installs, upgrades of installs which have device-mapper-multipath installed will still have it installed after the upgrade.

How To Test

1. Install F33 on a machine / VM
2. Do "rpm -q device-mapper-multipath", the output should be "device-mapper-multipath" is not installed

User Experience

Faster booting Fedora when installed from the livecd.

Dependencies

There are no other changes / package updates this Change depends on; or which this change impacts.

Contingency Plan

• Contingency mechanism: Re-add device-mapper-multipath to the livecd if the dropping of it causes problems.
• Blocks release? No

Documentation

This change does not require any documentation.

Release Notes

FIXME