We can use the banner format here, to be coherent with the repository style.

You can provision them as a follow-up change, uncommented instead.

That comment can be safely removed: the pillar name and the ike_ esp_ keys make that clear what is it.

Jinja syntax allows to use dots as separator to access dictionary keys.

We can use it, but in that case, it's really coherent to use it everywhere.

Won't really work beyond the scope of a test tunnel between those two links. You need a more flexible way to pass the info according the node.

Besides, if you deploy this on both router-002 and router-003 you would get twice the config router-002 to router-003 it seems.

Header missing, see https://devcentral.nasqueron.org/source/snippets/browse/main/salt/file.conf

Header missing

That one doesn't exist in the change it seems

We can use explicit variable names.

One letter variables is an historical artefact, from the era where the maximal length for a specific code line was fixed.

See for example for COBOL this IBM documentation:
https://www.ibm.com/docs/en/developer-for-zos/15.0.x?topic=editing-setting-language-specific-maximum-line-length

Nowadays, best practice is to use clear variable name to facilitate reading the code.

What's the role of the router? I think it's to get public IP for that node.