Anycast provider for SMTP?

[mr.jonas.bjork at me.com (Jonas Björk)]

> On Jun 18, 2015, at 11:29 PM, Larry Sheldon <larrysheldon at cox.net> wrote:
> 
>> On 6/18/2015 16:25, Jonas Bj?rk wrote:
>> 
>>> Because clients will switch to unicast for renewal. Also clients will stay
>>> with the current server forever, so you might have a bad distribution of
>>> load between the servers. If one server was down everyone will switch to
>>> the other and never go back until forced.
>> 
>> Why wouldn't they go back to the nearest server when it comes back online?
> 
> Been awhile, but it seems like they try to "renew" the lease they have, with the server that holds it.
> 
> -- 
> sed quis custodiet ipsos custodes? (Juvenal)

The clients speak unicast with one single ip-helper which address is shared by all the servers.
They can't choose which ever server to talk to.