Shared mailbox with virtual domain

edusense.01

Hi,

I’m trying to wrap my head around shared mailboxes served below a virtual email domain.

The kopano installation is serving domain1.tld. This works fine. The shared mailboxes are created to use domain2.tld.
domain2.tld is defined in postfix as virtual, with a ‘catch all’ to redirect unknown recipients to a sink:

# Virtual
# Various entries for domain1.tld
@domain1.tld                  sink@domain1.tld

domain2.tld                   anything
# sales@domain2.tld           sales@domain2.tld            # Tried, SOFTBOUNCE
# sales@domain2.tld           shared_mailbox               # Tried, SOFTBOUNCE
sales@domain2.tld             shared_mailbox@domain1.tld   # Sink
shared_mailbox@domain2.tld    shared_mailbox@domain1.tld   # Never executed
@domain2.tld                  sink@domain1.tld

Postfix is configured to search on mail attribute to find users / mailboxes, shared_mailbox is defined in LDAP with mail attribute sales@domain2.tld.

Whatever I try, emails directed to sales@domain2.tld or shared_mailbox@domain2.tld either end up in the sink or with a status=SOFTBOUNCE (User unknown in virtual alias table)

Aliases are searched for both virtual and LDAP, ldap attributes with virtual email-addresses on shared_mailbox make no difference in outcomes.

I’m bumping my head. Apparently, I’m missing something obvious. Any ideas what that might be?