Adding Access Rules so only specific IP ranges can hit port 25

We have a Cisco ASA Firewall and Exchange 2013. We're utilizing Barracuda's cloud-based SPAM filtering solution but SPAM is still coming in outside of the SPAM filter. Barracuda recommended limiting their IP ranges being the only IPs that can hit port 25 ( and

I know enough to configure but really would love some help on adding the Access Rules on the ASA.

Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Patrick BogersDatacenter platform engineer LindowsCommented:

Maybe it is easier to configure in exchange so your recieve connector only accepts forwarded mail from Barracuda range?
Very easy to configure.


Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
I would create a new network group and add the two networks to that group. Go to the existing security rule that allows inbound port 25/SMTP, and change in source IP from any to the new group that you created.

If you need further assistance, you can contact Cisco TAC or submit a Live request here in E-E.
pstiffsaeAuthor Commented:
@Patrick Bogers - I'm fairly familiar with updating the receive connectors but am a but rusty. By default, we have Client Front End EMAIL (server name is EMAIL) - Frontend Transport, Client Proxy EMAIL - Hubtransport, Default EMAIL - Hubtransport, Default Frontend EMAIL - Frontend Transport, Outbound Proxy Frontened Email - Hubtransport. All are currently setup to allow ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff​ to receive e-mail from these remote IPs.

@kevinhsieh - I'll check the firewall and see if I can't schedule a Live request as well
Big Business Goals? Which KPIs Will Help You

The most successful MSPs rely on metrics – known as key performance indicators (KPIs) – for making informed decisions that help their businesses thrive, rather than just survive. This eBook provides an overview of the most important KPIs used by top MSPs.

Patrick BogersDatacenter platform engineer LindowsCommented:
Hi pstiffsae,

Check the one that is serving on port 25, it is only one (prob Default Frontend)

pstiffsaeAuthor Commented:
Thank you for helping me get this resolved!
FYI, document this well! As someone coming in, I would expect this to be restricted at the perimeter firewall.
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.