Configuring Relaying

There are several situations in which you may not want your Citadel server to deliver mail directly to recipients over the public Internet. These include:

• Your organization requires all outbound mail to be sent through a relay
• You want to use an outbound mail filtering/scanning service
• You are on a private network and your ISP requires all outbound mail to be sent through their mail server

If this is the case, you can relay all outbound mail through a smart host. You can configure a smart host two ways:

• From WebCit, select "Administration" -- "Domain names and Internet mail configuration" -- "Smart hosts"
• From the text client, select .Admin System-configuration Internet , and add a smart host.

You can specify just a host name or IP address, but if you need to add a port number, username and password, or SMTPS instead of SMTP, you can specify a valid SMTP URI, such as:

 [smtp[s]://][username:password@]host[:port]

For example, if your relay is at relay2.provider.com and is on port 587 and you have to log in with username joebloggs and password 12345 your SMTP URI would be:

 smtp://joebloggs:12345@relay2.provider.com:587

But what if your username has an @ in it? If so, replace the @ with %40 and it will work. For example, if your username in the above example was joebloggs@mydomain.com then your SMTP URI would be:

 smtp://joebloggs%40mydomain.com:12345@relay2.provider.com:587

Using multiple smart hosts

If you configure multiple smart hosts, one will be selected at random for each message that is delivered. If one of them is unavailable, the others will be tried. This allows some fault tolerance if your relaying service offers you multiple hosts.