Anycast provider for SMTP?

[larrysheldon at cox.net (Larry Sheldon)]

On 6/18/2015 16:40, Jonas Bj?rk wrote:
>
>> 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.

> 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.

One of us is confused (and it may well be me) but I thought the 
ip-helper address was only useful in the initial grope-in-the-dark for a 
server that is not on the local Ethernet broadcast domain.

Thereafter the negotiations (I thought) are between the client and the 
responding server and forever after until a failure-to-renew occurred.

-- 
sed quis custodiet ipsos custodes? (Juvenal)