Avatar of king daddy
king daddyFlag for United States of America

asked on 

Help with accepted domains and emails to nonexistent accounts

We have 6 authoritative domains and 8 internal relay domains in a hybrid exchange environment (one 2013 server on prem and office 365 hosted email server). Out default domain is internal relay (fyi). The issue is that we are seeing emails coming in to non-existent email addresses being bounced back between our server and a barracuda spam appliance. This is filling up the queue. While it is causing a negligible delay, I have been tasked with figuring out what if any impact we would see by changing our internal relay domains to authoritative and if it would prevent the bouncing of emails between the server and the barracuda. We are looking to just dropping emails coming in to nonexistent email accounts.

Thanks for any assistance as I have not had to previously deal with this. Other methods of stopping the emails from bouncing between the server and barracuda and just being dropped are welcomed.
ExchangeMicrosoft 365

Avatar of undefined
Last Comment
king daddy
ASKER CERTIFIED SOLUTION
Avatar of timgreen7077
timgreen7077

Blurred text
THIS SOLUTION IS ONLY AVAILABLE TO MEMBERS.
View this solution by signing up for a free trial.
Members can start a 7-Day free trial and enjoy unlimited access to the platform.
See Pricing Options
Start Free Trial
SOLUTION
Avatar of David Favor
David Favor
Flag of United States of America image

Blurred text
THIS SOLUTION IS ONLY AVAILABLE TO MEMBERS.
View this solution by signing up for a free trial.
Members can start a 7-Day free trial and enjoy unlimited access to the platform.
Avatar of king daddy
king daddy
Flag of United States of America image

ASKER

Thank you both, timgreen7077 and David, for the quick replies.

I would like to verify whether we are experiencing NDRs bouncing between the barracuda and the server or the actual email sent to a nonexistent email address being "bounced" between them. I suspect the latter. My language may have been misleading regarding what we are experiencing. If indeed the latter, I will check the barracuda's recipient filtering capabilities as suggested.
1-check barracuda's SSL Certifications
2-Add SPF records to all of your sender domains
3- check Send / receive connector authentication s
4-check domains & public IP's if got blacklist
Avatar of king daddy
king daddy
Flag of United States of America image

ASKER

Just wanted to update this. Someone else is working on it now as there are other, more pressing issues.
I did find out that recipient filtering on the barracuda messes with some sort of SMS messages that go through the barracuda for another domain we process.
Thanks for the info.
Exchange
Exchange

Exchange is the server side of a collaborative application product that is part of the Microsoft Server infrastructure. Exchange's major features include email, calendaring, contacts and tasks, support for mobile and web-based access to information, and support for data storage.

213K
Questions
--
Followers
--
Top Experts
Get a personalized solution from industry experts
Ask the experts
Read over 600 more reviews

TRUSTED BY

IBM logoIntel logoMicrosoft logoUbisoft logoSAP logo
Qualcomm logoCitrix Systems logoWorkday logoErnst & Young logo
High performer badgeUsers love us badge
LinkedIn logoFacebook logoX logoInstagram logoTikTok logoYouTube logo