Exchange 2003 SMTP

Posted on 2011-09-14
Medium Priority
Last Modified: 2012-06-27
we have an exchange server 2003, they call SMTP server, but I am not sure the right role it has.
it has exchange 2003 installed on  it. I know that the email goes through it to internet.
But there is confusion in SMTP roles:
SMTP connectors
SMTP Gateway
SMTP virtual servers
Smart Host
SMTP Relay
........and maybe more

I know I have given you too much info, that I need to find out, but I know that emails sent to internet go through this server, and this server is called an smtp server.

Any way to find the right role of this server?

Question by:jskfan
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LVL 37

Accepted Solution

Jamie McKillop earned 2000 total points
ID: 36540150

Exchange 2003 doesn't have roles like Exchange 2007/2010. You can configure it as a front-end and back-end if you want to route all client traffic through a front-end server but that isn't really a separation of roles like 2007/2010.

The terms you have listed aren't roles. They are components and functions of an SMTP server.

SMTP Connector - this is an object that is created on an SMTP server to specify rules on how mail is to be routed when it is sent to spefic domains. For example, you might setup an SMTP connector in Exchange to route mail to external domain by perdorming a DNS lookup and sending directly to the recipient's server. Alternatively, you might setup that connector to route all external mail through an SMTP appliance that does spam and A/V filtering. You can see the connectors that have been setup in Exchange 2003 ESM by expanding Message Routing Administration - Routing Groups. Expand each routing group and you will see a Connectors folder.

SMTP Gateway - this is the SMTP server that is used to transfer mail to and from external domains. It is the point of contact between your organization and external SMTP servers. For example, the previously mentioned SPAM and A/V appliance would be an SMTP Gateway.

SMTP Virtual Server - This is the SMTP instance that is running on the Exchange server. You can have multiple SMTP virtual servers on an Exchange server but each one must run on a unique port or IP address. Exchange has a default SMTP Virtual server and you would genrally only create additional SMTP virtual servers in special instances like if you need to force TLS encryption to a specif external domain. You can see the virtual servers in ESM by expanding Administrative Group then in each Adminstrative Group, expand each server then Protocols - SMTP.

Smart Host - You SMTP send connector can be configure to route email based on DNS lookups or it can be use to route all email through a Smart Host. The Smart Host then takes care of routing the email to the destination. In the previous examples the SPAM and A/V appliance would be the Smart Host. In ESM, you can see if your SMTP connectors are using a smart host by opening the properties page for each connector and looking on the General tab. If the radio button beside 'Forwal all mail through this connector..." is checked and there is an IP or host name in the field below, you are using a smart host.

SMTP Relay - Normally, Exchange would be setup to only accept messages destined for its own domains but you can configure it to allow connections from other servers and Exchange will route the message to the external domain. You would generally secure this by IP or by an authentication mechanism to prevents spammers from using you as a relay. You can check you relay setting in ESM by opening the Properties page of each SMTP virtual server and clicking Relay on the Access tab.


Author Comment

ID: 36541182
I guess it is used to scan email that comes in, but I see exchange information store service running on the server. Does it mean there is full blown exchange installed there with Databases?

Author Comment

ID: 36541674
I guess it is an SMTP relay
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Author Comment

ID: 36541697
I amnot sure why it is blocking emails going out to the internet?
It makes sense when it blocks emails coming in from outside to inside, but not the other way around.
LVL 37

Assisted Solution

by:Jamie McKillop
Jamie McKillop earned 2000 total points
ID: 36542170
Make sure you have an SMTP connector setup for the * address space that uses DNS to route. Make sure your SMTP relay settings are configured to allow the servers that are using it to relay.


Author Closing Comment

ID: 36547460

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