Installing jessie/buster machines with stretch FAI?

[Sébastien Grenier]

Hello,
I'm running fai-server 5.7.3 on Debian stretch and  I've been installing
stretch machines without problem.  I'm using the default.profile menu to
choose which profile to install.

Now I would like to have the same setup of profile but with jessie
instead stretch.  I tried to modified
https://github.com/faiproject/fai-config/blob/master/class/DEBIAN.var#L1
(release=) to have there "jessie" instead of "stretch". No change,
stretch is always installed... I'm curious about how this variable is
useful then.

I looked at changing the sources.list on the faiserver here
/srv/fai/nfsroot/etc/apt/sources.list from stretch to jessie! I'm
getting jessie packages on the client machine but dependencies errors.

I feel that is far from the right way to do this...  and soon, I'll like
to test installing buster (testing) with the same profile setup. What
would be the good way to install another debian release than "stable".

Cheers,

Sébastien