identify 143 vs 993 clients

[@lbutlr]

On 25 May 2020, at 12:48, mj <lists at merit.unu.edu> wrote:
> I would then ask them to move over to 993, and finally disable port 143 altogether.

From personal experience the only way to do this is to stop listening to port 143. I dropped support for non-encrypted mail ports ages ago, and I didn't get a single user to switch from 143 to 993 until I disabled 143.

Send an email to your users "You must make this change bu (date+2 days)" and then drop port 143 in 2 days as promised. If you have a web server, but a large red box on it "Can't login?" With a link to the email you sent.

(And do not allow users to send mail un-encrypted either, force them to use 587 or 465 by not accepting user mail on port 25).



-- 
This is Art holding a Mirror up to Life. That's why everything is
	exactly the wrong way around. --Wyrd Sisters