Dns_trusted_acl for Maas

I was trying to figure out the syntax to get/set the dns_trusted_acl parameter, and wasn’t having luck finding the appropriate documentation.

For reference:

To read:
maas $profile maas get-config name=dns_trusted_acl

To write:
maas $profile maas set-config -d name=dns_trusted_acl value=0.0.0.0/0

To reset:
maas $profile maas set-config -d name=dns_trusted_acl value=

My question is, where are the docs for this option (and others like it), so we can use them in future? Also, for this particular option, what is the delimiter for multiple values (e.g. would 10.0.0.0/8;172.16.0.0/12;192.168.0.0/16 work)?

This feature is mentioned in the following release notes: Development Update - August 2018, which in turn mentions bug LP: #1774206.

Looking at the MP [0], the code in the current master is the same [1]. Since it just uses plain vanilla split it seems to indicate that the list in the config should be space-separated then.

It would be good to document this for users, as well as adding it to the config description in [2].

[0] https://code.launchpad.net/~andreserl/maas/+git/maas/+merge/347398
[1] https://git.launchpad.net/maas/tree/src/maasserver/dns/config.py#n149
[2] https://git.launchpad.net/maas/tree/src/maasserver/forms/settings.py#n419