I don’t know if am I writing to the correct category. I just faced with the dramatically slow boot system which was installed by Maas server (version 2.7) which unavailable during the boot.
I think this is a catastrophic bug when the system doesn’t ping MAAS and then try to run each init-script. 2 hours long! This is awful software.
To fix it I entirely recommend to run command right after the system booted from the disk:
apt purge cloud-init