I've a non-profit with split hosting for its email services and its website.
It has also been approved for hosting by Dreamhost. Dreamhost's email service and its management suit this non-profit.
Now I want to shift just the needed DNS records from the non-profit's current email host to Dreamhost (along with the actual hosting, of course) but not change the addresses for the web hosting side from the separate web host. The registrar for the domain-name involved is a fourth party, neither Dreamhost nor either of the two current hosts.
I am hoping I need only change some A-records but cant find any examples or other reassurance. The email hosting is managed via a subdomain labeled "mail."
The current email host does not use cpanel, which an earlier thread on this forum suggested means the steps to transfer the mailbox contents is not an automatic one via my Dreamhost cpanel. Sigh* The "more complicated" alternative was not described however.
The current email host for this non-profit maintains about 400+ mailboxes of which perhaps 85 are active. Present plans contemplate moving only 50 of those mailboxes, perhaps 25 of which have virtually no stored emails except probable SPAM which need not be moved.
But it would be good to know how to transfer the whole set of 400+, as we could then use Dreamhost to archive and then delete the no longer supported mailboxes. Some of those unsupported mailboxes will be replaced by Dreamhost served forwarders but neither webmail nor storage after deletion are needed for those otherwise unsupported usernames. (I know how to set up forwarders once the domain points at Dreamhost.)
Can someone point me to a walk through for the right order in which to arrange this changeover, to preserve service largely uninterrupted for at least the 50 mailboxes we want to move? The wiki.dreamhost entries about shifting hosts talk largely about combined email and hosting, all shifted at once with one domain. I only want to move the email side, and even then perhaps only as subset of current mailboxes and their content.
Thanks for any advice