We are transitioning from IronMail 6.7.2 to MEG 7.6. We have four MEGs for inbound and four for outbound. Our mail servers are Domino 8.5 running on iSeries.
We are running into a problem with outbound mail backing up on the Domino servers - especially the Domino servers that do a little higher volume. We'll see 3000+ messages backed up on Domino. If we take that Domino server and point it to our 6.7.2 outbound mail gateway, it clears out in 10 minutes. We tried using the store and forward configuration and that didn't help. We do maybe 70-80,000 messages per day on our higher volume outbound gateways. We never had any problems on 6.7.2.