Sep 21 14:04:28 qemuarm sshd[381]: pam_systemd(sshd:session): Failed to create session: Connection timed out https://autobuilder.yoctoproject.org/typhoon/#/builders/110/builds/2921/steps/13/logs/stdio qemuarm-alt ubuntu1804-ty-1
We also suspect that this is related to not being able to limit the load on dunfell builds. So if we can fix that and wait a month or two to see if this happens again.
There hasn't been another occurrence and we have limited load somewhat by using 'make -l'.