Boot critical chain systemd
Show the serialized dependency chain that actually delays boot; more honest than blame
systemd-analyze critical-chain <unit>
more systemd
all 26 commands →
Boot timeline SVG
systemd-analyze plot > boot.svg
Drop-in override
systemctl edit <unit> # writes /etc/systemd/system/<unit>.d/override.conf
Reload unit files
systemctl daemon-reload
Mask a unit
systemctl mask <unit> && systemctl unmask <unit>
Recursive dependency tree
systemctl list-dependencies <unit> --all