Comment 19 for bug 1851276

WRT your other question. Your failures are happening when cloud-init tries to install a set of packages required for maas_run_remote_scripts to run. It appears that only main is getting configured and the packages MAAS needs are from updates and universe. Because of that failure maas_run_remote_scripts never runs.

The reason maas_run_remote_scripts checks if apt cache is available before running apt update is so its only done once and only when its needed. Apt checks if the cache is out of date based on the system time, if NTP isn't configured this could be wrong so cloud-init/MAAS needs to ensure this happens before any package is installed. Once its done we don't want it to happen again as that will cause additional load on the apt server and network traffic.