Brightmail spam definitions not updating
Select the server that you wish to create the receive connector on. Exchange names the various default connectors using a standard of “Purpose SERVERNAME”, for example “Client Frontend E15MB1”. If the server you chose is multi-role you'll need to select the Frontend Transport role.
Remember, the server should be either a multi-role server or a Client Access server. If the server is CAS-only then Frontend Transport will already be selected. For servers with a single network adapter the default binding will usually be fine.
The Client Access server role hosts the Frontend Transport service, which provides filtering of email traffic (eg antispam agents), and routing of email between the internal Exchange servers and the outside world The Mailbox server role hosts two additional services: Get-Service | Where Display Name -like "*Transport*" | Select Display Name Display Name ----------- Microsoft Exchange Frontend Transport Microsoft Exchange Mailbox Transport Delivery Microsoft Exchange Mailbox Transport Submission Microsoft Exchange Transport Microsoft Exchange Transport Log Search No matter whether the server is multi-role or only installed with the Client Access server role, the Frontend Transport service is the only service already listening on TCP port 25 (SMTP).
Looking at the Exchange 2013 transport architecture there are multiple services involved.
Here is an example of what happens if I use Telnet to try and send an email to an address that is external to the organization.
220 E15MB1.exchange2013Microsoft ESMTP MAIL Service ready at Tue, 1000 helo 250 E15MB1.exchange2013Hello [192.168.0.181] mail from: [email protected] 2.1.0 Sender OK rcpt to: [email protected] 5.7.1 Unable to relay Receive Connectors.
False False As with the internal relay example I recommend creating a DNS record for a generic name for SMTP.
For most environments there is no need to create separate DNS names for internal vs external SMTP.