Hi,

I need to run two Dovecot instances with totally different authentication configs: first - passwordless, based on client SSL certificate; and second - regular password based (LDAP, passwd etc.). (As far as I know this cannot be achieved with single Dovecot instance; if I'm mistaken, please correct me). My intention is to give clients dual access to their mailboxes: some do own a SSL cert, others do not.

I want to know whether it is possible at all. If possible, how do we implement proper concurrent access (locking, etc.) between the two instances to a single maildir-based store? I guess this should be possible since I know Dovecot can operate NFS-backed mail stores, e.g. in a load-balancing cluster setup.

Second, is it OK to run the second instance in the same OS (we use Linux)? or chroot'ed or even virtualized solution will work better?

Thank you! Zohan