Solved

Exchange SMTP relay/gateway

Posted on 2011-09-20
3
715 Views
Last Modified: 2012-06-27
---If I understand SMTP gateway or some call it SMTP relay, is where the anti virus and anti spam software is installed on the same box as exchange2003 (without mailboxes), so that emails coming in from internet are scanned before they are forwarded to the Front end server.
correct me if I am wrong

--emails going from inside to internet should not go through this SMTP gateway/relay, but have seen some configuration that make it go through it. what 's the reason ?

---if possible, can someone tell me how Exchange Front end is able to determine such email has its user mailbox in Exchange server 1 and such email has its user mailbox in exchange server 2  ???

thanks
0
Comment
Question by:jskfan
3 Comments
 
LVL 9

Accepted Solution

by:
jebeckham earned 250 total points
Comment Utility
Your description is correct about SMTP gateway or relay.  It need not necesarly scan for viruses/spam/malware but it can.

Some organizations choose to send their outbound email through an SMTP gateway or 3rd-party service as to reduce the risk of their internal users or applications from sending out viruses/spam/malware to clients, custoers, partners, etc.

If you have one front-end or hub transport server and two back-end or mailbox servers, the FE/HT servers have access to information within Active Directory to determine where the user's mailbox is stored and therefore can make an intelligent decision about where to deliver the inbound message.

I hope that helps!
0
 
LVL 28

Assisted Solution

by:sunnyc7
sunnyc7 earned 250 total points
Comment Utility
a) Not-necessary.
Messages can be scanned through a hosted anti-spam solution and then delivered to your exchange server.
Depends on how you setup your MX records.
Emails will hit the first-record on your MX first.
If it's hosted anti-spam like postini, then they will scan it first and exchange is hidden from the public.
If it's exchange server, then you have to take care of hygiene issues on Exchange.

b) Different AV solutions handle it differently.
Some quarantine.
Some do a "on arrival" and "before arrival" filtering.
-------------

--emails going from inside to internet should not go through this SMTP gateway/relay, but have seen some configuration that make it go through it. what 's the reason ?
>> Emails will go out through SMTPSVC1 (default smtp virtual server)
Some AV solutions "bing" to that, and use outgoing emails to whitelist. (General assumption is, if you your org is sending someone emails, you probably do business with them - hence whitelist.)

----
---if possible, can someone tell me how Exchange Front end is able to determine such email has its user mailbox in Exchange server 1 and such email has its user mailbox in exchange server 2  ???
>> Depends on your exchange-org setup and how the topology is configured.
Gen speaking, you can look up the raw data in ADSIEdit.msc

start> run > adsiedit.msc
Configuration > services > Exchange > my org > first admin group etc
Check a list of servers.

Exchange will check all available non-front-end servers in Ex03 and try to deliver mails to those mailboxes.
0
 

Author Closing Comment

by:jskfan
Comment Utility
Excellent explanation----thank you guys!
0

Featured Post

Top 6 Sources for Identifying Threat Actor TTPs

Understanding your enemy is essential. These six sources will help you identify the most popular threat actor tactics, techniques, and procedures (TTPs).

Join & Write a Comment

We are happy to announce a brand new addition to our line of acclaimed email signature management products – CodeTwo Email Signatures for Office 365.
Find out how to use Active Directory data for email signature management in Microsoft Exchange and Office 365.
The video tutorial explains the basics of the Exchange server Database Availability groups. The components of this video include: 1. Automatic Failover 2. Failover Clustering 3. Active Manager
This video discusses moving either the default database or any database to a new volume.

772 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

14 Experts available now in Live!

Get 1:1 Help Now