Unfortunately there're no more info: one of the generator is failing but I
can't see which one.
The list of the generators is:
> systemd[414]: Spawned /usr/lib/systemd/system-generators/ibft-rule-generator as 415.
> systemd[414]: Spawned /usr/lib/systemd/system-generators/lvm2-activation-generator as 416.
> systemd[414]: Spawned /usr/lib/systemd/system-generators/nfs-server-generator as 417.
> systemd[414]: Spawned /usr/lib/systemd/system-generators/systemd-cryptsetup-generator as 418.
> systemd[414]: Spawned /usr/lib/systemd/system-generators/systemd-debug-generator as 419.
> systemd[414]: Spawned /usr/lib/systemd/system-generators/systemd-fstab-generator as 420.
> systemd[414]: Spawned /usr/lib/systemd/system-generators/systemd-getty-generator as 421.
> systemd[414]: Spawned /usr/lib/systemd/system-generators/systemd-gpt-auto-generator as 422.
> systemd[414]: Spawned /usr/lib/systemd/system-generators/systemd-hibernate-resume-generator as 423.
> systemd[414]: Spawned /usr/lib/systemd/system-generators/systemd-insserv-generator as 424.
> systemd[414]: Spawned /usr/lib/systemd/system-generators/systemd-openqa-generator as 425.
> systemd[414]: Spawned /usr/lib/systemd/system-generators/systemd-rc-local-generator as 426.
> systemd[414]: Spawned /usr/lib/systemd/system-generators/systemd-system-update-generator as 427.
> systemd[414]: Spawned /usr/lib/systemd/system-generators/systemd-sysv-generator as 428.
> systemd[414]: Spawned /usr/lib/systemd/system-generators/systemd-veritysetup-generator as 429.
It would be interesting to figure out which one fails.
You can do so by masking one generator by one and run "systemctl daemon-reload"
which should run all generators again assuming that the issue can be reproduced
while reloading systemd configuration.
To mask one generator you can do for example:
$ ln -s /dev/null /etc/systemd/system-generators/ibft-rule-generator