Hello, I have two completely independent ISPConfig3 setups running their own info. Think of it as two separate businesses. What I want to know is can I set them up to backup each others MX servers? What I am thinking is mx 10 for primary and mx 20 for secondary but do not store mail for each other only queue it in case a mail server is down at the moment so that the backup can simply forward the queued mail once back up. Hope that makes sense. Looking for proper way to configure each server to make it work under ISPConfig3
Have you tried relay recipients? BUt even if you use mx10 and mx20 this is no gurantee, that the sending server tries mx10 before mx20. And you should make sure, thatthe backup-mx accept mails only if the recipient exists on the primary mx (you can do this quite simple with the verfiy-service).
So in other words there is no easy way. Sure if I wanted to learn how to program ISPConfig then it could be done but there is no native way to do it. I don't have the 4 hours needed to make this happen so we will just continue to roll the way it is. Just thought it would be nice to have a backup server for each other.
This is not releated t ispconfig. You can use relay_recipient_maps (you can set the values within the interface) or set relay_recipient_maps to null and use the verify-service from postfix to check if the receiver-address exists. You should never run a backup-mx without validating the incoming mails. If you have already 2 mx wit amavis etc., just configure postfix´verify-service and add reject_unverified_recipient before permit_auth_destination, permit_mx_backup or permitand AFTER verify outgoing mails (permit_mynetworks, permit_sasl....)
