Cloud-init "no datasource found" during commissioning

You can always fallback to PPA, but even with a snap version of MAAS it is possible to apply certain changes, repack snap and try things out.

root@maas:/var/lib/snapd/snaps$ snap install maas
root@maas:/var/lib/snapd/snaps$ unsquashfs maas_xxx.snap
# do the changes to rackd.nginx.conf.template
root@maas:/var/lib/snapd/snaps$ snap pack ./squashfs-root
root@maas:/var/lib/snapd/snaps$ sudo snap install --dangerous maas_xxx.snap
root@maas:/var/lib/snapd/snaps$ snap connections maas | awk '$1 != "content" && $3 == "-" {print $2}' | xargs -r -n1 sudo snap connect
root@maas:/var/lib/snapd/snaps$ sudo maas init region+rack --database-uri maas-test-db:///

Here is a related post: