[Mailman-Users] Fwd: Warming IP Addresses -- Gradually Increasing Email Volume

[Alexander Neilson]

Hi Craig

> 
>> On Wed, Feb 22, 2017 at 7:23 AM, Keith Seyffarth <weif at weif.net> wrote:
>> 
>> Greg Sims <greg at headingup.net> writes:
>> 
>>> Thanks for your feedback Carl.  Here is some additional information about
>>> our environment.  We have a single server in a commercial data center
>>> (Softlayer).  "Communicating" to the ISPs is a challenge.  No reply to
>>> email and no way to discuss something like this on the telephone.  The
>> only
>>> answer is to construct a strategy that does not raise a "red flag".

Are you already using DMARC / DKIM to sign all messages? One of the mailop people from a big mail provider mentioned that if you have this configured and it has a reputation then provided you retain the same key and the other details the same the reputation you have will be tracked and follow that along. 

This obviously requires this configuration to be setup however if you have some time left before you decommission then you could get this in place to attract your existing reputation to the key and help (nothing is perfect but all of this is a numbers game)

While I haven't seen this talked about specifically on top of the above (in a belt and suspenders kind of way) keeping the same forward / reverse / EHLO name for your new server as the old (provided the old has these configured to your domain) this could provide another signal that this is the same system doing the same job just moved to a new IP Address. 

Nothing here will be perfect and if you have the time warming up the new IP (perhaps setting up the new server's MTA possibly needing different name in this scenario) and asking your existing server to pass off a small percentage of your email to that machine as an outbound relay and increase the number until close to all via the new server then complete the migration. 

I don't have a guide on the above myself as I haven't had to do this. But from all the advice I have seen on lists about this topic they seem to be ideas that will aid deliver ability.