Virtual alias address class and no_address_mappings

[Peter]

I'm not entirely certain if this is intentional or not, but I ran across 
this one with someone in IRC just now.

If someone uses virtual_address_domains and has 
"receive_override_options = no_address_mappings", then postfix will kick 
back an error of "User unknown in virtual alias table" for any recipient 
in that domain.  This is probably because postfix doesn't load or access 
virtual_alias_maps if no_address_mappings is set.  This can be 
problematic in the following scenario:

User has a content filter configured which re-injects to postfix on 
another port which does not have no_address_mappings set.  The intent 
here is for address mappings to be ignored and the content filter run 
initially then upon re-injection for the address mappings to be 
processed and the message routed as appropriate.  Because 
no_address_mappings is set and the recipient address is in the virtual 
alias address class, however, the message instead gets rejected 
initially with the above mentioned error.

A better approach might be to read the virtual_alias_maps in order to 
allow the message to pass the recipient check but to still not use it 
for address mappings if no_address_mappings is set.

Is this behavior intentional or just a side effect of how 
no_address_mappings is implemented?


Peter