digint/btrbk

btrbk.timer runs too soon during boot process

Open

#486 opened on Jul 22, 2022

View on GitHub
 (8 comments) (0 reactions) (0 assignees)Perl (2,076 stars) (136 forks)batch import
help wanted

Description

As is, btrbk.timer runs so early during the boot process that the hostname hasn't even been assigned yet. This also happens long before vital services are started.

To demonstrate, shut the backup server down before midnight and boot after midnight. Then run:

journalctl --since 0:0:0

Notice that btrbk runs in the midst of everything slowly being started up. On my fedora-36 system the hostname was still the temporary boot placeholder name of "fedora" instead of its actual hostname. The network wasn't up and dns wouldn't have been working either. I'm not sure what one is supposed to wait for boot to finish under systemd.

edit: I had thought OnActiveSec=2min in addition to OnCalendar=daily would take the union of the two constraints, but that doesn't appear to be the case.

Contributor guide

Tech stack
shell
Domain
devops
Issue type
bug
DifficultyEstimated implementation difficulty for a new contributor, from 1 for very small changes to 5 for expert-level work.
3
Estimated timeA rough time range for an experienced contributor to investigate, implement, test, and prepare a pull request.
1-3 hours
Activity statusHow available the issue appears right now: fresh, active, stale, blocked, or waiting on maintainer input.
stale
ClarityHow clearly the issue explains the expected change, acceptance criteria, and next step.
clear
Prerequisites
Understanding of systemd timer unitsBasic knowledge of btrbk configuration
Newbie friendlinessA 1-100 score estimating how approachable this issue is for first-time contributors.
30
Research direction
Examine the btrbk.timer file in the repository (likely under /usr/lib/systemd/system/ or in the source tree) to understand the current timer configuration. Research systemd timer options like OnActiveSec, OnBootSec, and conditions such as ConditionPathIsReadWrite or After=network online.target. Consider adding a condition to defer the timer until after the hostname is set and network is up. See also systemd timer documentation and existing discussions in the issue comments.