I have a debian server which uses exim4 as mta and courier-imap to allow users to read main. Mail is usually either delivered locally or an aliases file is used to forward mail to another adress. e.g.
# Local account: foo receives mail for foo@domain.com
somealias: bar@otherdomain.com
otheralias: foo, bar@otherdomain.com # Deliver both locally and remote
We now have an emailadres which we would like to be accesible through imap, but also be forwarderded to another e-mail address. This can be achieved by renaming the account and using the aliases file, but is this also possible with the local account having the same name? Renaming the account would require quite some reconfiguration in several systems.
# buz@domain.com needs to be de delivered to both baz@otherdomain.com and the "buz" local account
# Possible solution, rename buz account to buzdummy, but this would case other problems
buz: baz@otherdomain.com, buzdummy
Just do what you start in alias file - without renaming:-)
If alias is expand to self then it is not expanded in loop again but skipped, so mail be forwarded outside and delivered locally. (See Exim documentation ).