Decrement "Max-Forward" header field

Is there a way to tell asterisk not to reset the max-forward value?
instead it should lower the field value by one.

That field is there for SIP proxies. Asterisk is a back to back user agent, and so the outgoing request is completely separate from the incoming one, which need not be a SIP one.

but in a loop asterisk would rest the field and the loop would never end. In complex sip networks this is a limitation.

I think it is worth a feature request.
you could set “maxforwards=decremet” in sip.conf at peer basis.

what do you think ?

You need to raise features requests without supporting code on the developer mailing list. You need to be aware that the SIP code is being replaced in the next major version. and feature requests will only be implemented against the new code.

Although I think that the outgoing channel technology driver can detect the private data structure for a same technology incoming channel, that is only true if there are no intervening agent or local channels.

Thank you !