Mirroring External Mailing Lists (two-way)

Two-way mailing list mirroring

Web Crossing can receive mail from an external mailing list and archive the incoming messages in folders and discussions. Also, Web Crossing can use its built-in SMTP server feature to send posted messages out to mailing list servers.

You can also set both ways at once and generate full two-way traffic between a Web Crossing conference folder and an external mailing list server.

The settings are the same as described in the incoming mailing list and outgoing mailing list setups - you just need to set both at once. However, if you are not careful in the setup of your mailing list subscriber lists you can run into a frustrating problem:

A Problem Scenario

A message is posted to the web forums.
That message is automatically sent to the external mailing list server.
The mailing list server sends the message to all subscribers, including Web Crossing itself!
Web Crossing checks its POP3 mailbox for new messages and receives the incoming message and posts it the conference again. Now two copies of the same message appear in the same discussion.

There are two solutions to this problem. The easiest solution is to just use the built-in email list server feature. With Web Crossing, there is a very flexible built-in mailing list server and everything is automatic. If you are anticipating a two-way mirroring, and would like users to be able to subscribe to any folder hierarchy as a mailing list, allow user-settable digest times, be able to send out notifications with URLs to bring people back into the web forums and other features like this, you should consider using Web Crossing's built-in email list server instead of an external email list server. You can see more details about setting up Web Crossing's built-in email list server in section one.

So, why bother using an external mailing list server since Web Crossing has a built-in mailing list server? There are several reasons for this:

Perhaps the main reason is historic. In previous versions, Web Crossing did not have its own built-in mailing list server, so people had to use external mailing list servers. So for backward compatibility, this feature is preserved.
It is also sometimes convenient to be able to mirror an existing mailing list, even when the mailing list exists outside of Web Crossing. This feature allows you to provide searchable web archives for any mailing list, any where in the world.

Another solution, if you want to mirror both ways using an external email list server, is to actually maintain two mailing lists. One mailing list contains all the subscribers including Web Crossing's POP3 mailbox address. New messages mailed in by subscribers are sent to this mailing list.

The second mailing list contains all the subscribers except for Web Crossing's POP3 mailbox address. This is the mailing list that Web Crossing sends mail to when a new message is posted to the web.

Most mailing lists are subscribed to by users sending a subscription request by email to the mailing list server. In the title or the body of the message you will typically see a command, such as "subscribe webxharbor-talk" (the actual command differs depending on the mailing list server you are using.)

The question, then, is how do you get new subscribers to subscribe to both mailing lists at the same time? The answer is to do it for them using WCTL (Web Crossing Template Language).