[Feature request] Add a (long) CNAME chain to the workbench

[tjeb]

Request came in via email:

It seems that different implementations handle long CNAME chains differently, where
BIND follows up to 16 CNAMEs while Unbound currently stops at 8 but will raise this
limit to 11 in the future.
I thought it would be helpful to have a long CNAME chain as part of the workbench
to make testing for this easy.

[tjeb]

This is a good suggestion. Since the chain can be static, we could create a static zone for this (such as 'cnames.wb.sidnlabs.nl)

My first though was that we could have multiple cname chains (say, one of length 1, one of length 2, one of length 4, etc), but this can of course be rolled into one long one, counting 'backwards', as it were:

Something like:
cname-end A 192.0.2.1
cname-end TXT "You have reached the end of the line"
cname-1 CNAME cname-end
cname-2 CNAME cname 1
cname-3 CNAME cname 2
cname-4 CNAME cname 3
and so on, up to some high number.

Documentation should probably stress that CNAME chains were originally never supposed to be any longer than 1, though :)