- main server + 2 outgoing gateways + 3 incoming gateways
- all domains are set to Deliver locally if user exists: Disabled and Domain Location: External (use MX record)
- both domains (domain1 and domain2) are present in local server and their MX configuration is pointing to incoming gateways
- incoming gateways are configured in Antispam Bypass Gateways section
- User1@domain1 is sending email to user2@domain2
- His message instead of being delivered locally based on domain MX configuration and Antispam Bypass Gateways configuration is being passed to outgoing gateway
- Outgoing gateway is checking for MX configuration and it is passing message to incoming gateway which bounces message with Authentication is required for relay error which is a normal thing.
Scenario 2 (half hour later, no configuration has been changed, no mail services here restarted):
- user1@domain1 i sending email to testuser@domain2 (so we have identical domain MX configuration and only different test user created under domain2)
- His message is not being passed to outgoing gateway and it is being delivered to testuser@domain2 based on MX configuration and bypass gateway configuration present in main server configuration.
I'm trying to solve issue why first message instead of being delivered locally has been passed to outgoing gateway. Only thing which came to my mind is that there was some problem with domain MX configuration resolving. Can someone from SmarterMail devs say what SmarverMail is doing when there is some problem with domain configuration resolving?