email forward type "redirect" also delivers to original mailbox

dneuhaeuser

Hi,
when I set a redirect forward for a mailbox, mails are delivered to both original mailbox and forward destination.

I would expect this behaviour with forward type "cc", but with "redirect" mails should only be delivered to the forward destination, right?

how can we change this?

crpb

Did you check "stop processing"?

dneuhaeuser

sorry, I'm talking about forwards set in admin gui, not in inbox rules.

crpb

ahh alright, if as you said "redirect" is chosen it should behave like that i think.

are you using full NAME@DOM.TLD aliases? this would be the only pitfall i could think of where it does something silly (on the postfix side)

EDIT; and yes, it tried it. from internal and external i don't get anything delivered.

gromox-3.1.36.98c22a3-lp156.8.1.x86_64
postfix-3.8.4-150600.3.3.1.x86_64

root@gromi:~# cat /etc/postfix/grommunio-virtual-mailbox-alias-maps.cf
user = grommunio
password = ....
hosts = localhost
dbname = grommunio
query = SELECT mainname FROM aliases WHERE aliasname='%s' UNION select destination FROM forwards WHERE username='%s' AND forward_type = 1
root@gromi:~# postconf virtual_alias_maps
virtual_alias_maps = mysql:/etc/postfix/grommunio-virtual-mailbox-alias-maps.cf

dneuhaeuser

crpb

are you using full NAME@DOM.TLD aliases?

yes, any other format is not accepted anyway, isn't it?

EDIT; and yes, it tried it. from internal and external i don't get anything delivered.

I get mails delivered, but twice (to original mailbox and forward).

Just realized this is only happening to forwards for mailbox users that were synced via LDAP.
On all these mailboxes I have the primary email address listed again under the "smtp" tab.
This is probably the cause!?

WalterH

dneuhaeuser his is only happening to forwards for mailbox users that were synced via LDAP.
On all these mailboxes I have the primary email address listed again under the "smtp" tab.

There is something wrong with your LDAP configuration or the data in LDAP/AD. The SMPT tab shows the content of the LDAP attribute proxyAddresses. Your own email address should never be included in the LDAP attribute proxyAddresses, only your aliases.

dneuhaeuser

WalterH Your own email address should never be included in the LDAP attribute proxyAddresses, only your aliases.

This AD previously had a MS Exchange Server running, which by default added the primary email address to the attribute proxyAddressesas well.
So I think I just have to remove these duplicate addresses in AD !?

WalterH

I have never seen the primary email address also used as an alias, not even in an Exchange installation. That doesn't make sense, unless you want to receive every email twice.

dneuhaeuser

WalterH I have never seen the primary email address also used as an alias, not even in an Exchange installation.

Well it is actually normal behaviour in Exchange:
https://techcommunity.microsoft.com/blog/exchange/fun-with-changing-e-mail-addresses/609781

proxyAddresses
This is the main attribute where e-mail address information is kept.
[...]
When the type is in uppercase letters, the address is considered to be the primary address of that type and it is used as the default reply address of that recipient.
When the type is in lowercase letters, the address is considered a secondary address and is used to resolve addresses during e-mail delivery, allowing the same recipient to receive e-mails directed to different e-mail addresses.

Since the behaviour in Grommunio seems to be different, I think this should be made more clear for users migrating.
Ideally the LDAP sync would filter these duplicates...

crpb

i use this type of format w/o any problems aswell with active directory

examplatory ldap entries:

mail: crpb@clownflare.de
proxyAddresses:
- SMTP:crpb@clownflare.de
- smtp:alias1@clownflare.de
- smtp:alias2@clownflare.de

EDIT: as a side-node, this is supported since end of '22 so nothing new about it 😛

dneuhaeuser

crpb
did you test a redirect via admin GUI in this constellation?

Since I removed the primary address from the field proxyAddresses, the redirects are working as expected here.

I had no other issues with the proxyAddress, just the redirects produced doubled messages.

I think the SQL UNION used in /etc/postfix/grommunio-virtual-mailbox-alias-maps.cf needs to be improved for this specific constellation.
SELECT mainname FROM aliases WHERE aliasname='%s' UNION select destination FROM forwards WHERE username='%s' AND forward_type = 1

crpb

I just looked again in my ldap-props and saw i someday changed it to just list the aliases w/o the prefix. Will do some tests and get back to you and/or will create a issue on github if it seems to break stuff.

UPDATE: https://github.com/grommunio/admin-api/issues/58