Changes/DisableDmraidOnFirstRun

Disable dmraid.service on first run if no dmraid sets are found

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.

Dmraid 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.

Fedora only support these RAID sets when they are already configured in the BIOS at installation time. So we can solve the problem of dmraid.service still depending on the obsolete udev-settle service by making dmraid.service disable itself if no supported RAID sets are found on its first run.

Owner

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

Current status

• Targeted release: Fedora 33
• Last updated: 2020-06-29
• FESCo issue: <will be assigned by the Wrangler>
• Tracker bug: <will be assigned by the Wrangler>
• Release notes tracker: <will be assigned by the Wrangler>

Detailed Description

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

Dmraid is necessary to support firmware-raid (motherboard BIOS built-in RAID support) for non Intel firmware RAID sets. These RAID sets are quite rare and we have never supported configuring these RAID sets after the installation without manually setting it up. Since we only support these sets when they are already configured in the BIOS at installation time, we can solve the problem of dmraid.service still depending on the obsolete udev-settle service by making dmraid.service disable itself if no supported RAID sets are found on its first run.

Note then when installing from the server or everything netboot isos, dmraid 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 dmraid to the installation package-set as necessary for the storage found at installation time. This means that for such installs, if a dmraid set is later configured, the user manually needs to install dmraid to be able to use the RAID set. This change adds a similar requirement to livecd installs, there the user will now need to do a "systemctl enable dmraid.service" if a dmraid set is added to the system later.

Scope

• Proposal owners:

• Other developers: N/A (not a System Wide Change)

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

• Policies and guidelines: N/A (not a System Wide Change)

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

Upgrade/compatibility impact

N/A (not a System Wide Change)

How To Test

N/A (not a System Wide Change)

Dependencies

N/A (not a System Wide Change)

Contingency Plan

• Contingency mechanism: (What to do? Who will do it?) N/A (not a System Wide Change)
• Contingency deadline: N/A (not a System Wide Change)
• Blocks release? N/A (not a System Wide Change), Yes/No
• Blocks product? product

Documentation

N/A (not a System Wide Change)