I don’t think it’s easy to migrate mail accounts from one provider to another in one hit. We did it here in the last couple of weeks from a cPanel to a Qmail system but, because each has a different feature set (among other things) it was easier to set up all the mail accounts afresh. As there was no IMAP data to move, it was just a matter of ensuring that user names and passwords were added correctly before re-directing the mail traffic and altering the client machines. Your scenario might be different tho…

I’ve never heard of anyone moving from Virtualmin to cPanel (but maybe folks wouldn’t mention it to us, since it might hurt our feelings). But, I can tell you a few things about Virtualmin and the way it deals with mail users, and that might help you with the process.

Virtualmin uses Postfix, with a virtual user map file (/etc/postfix/virtual), while cPanel uses Exim, I think. I’m pretty sure modern cPanel versions use Maildir, so the actual mail file format is the same–even if the locations are different. So moving the actual mail should be very simple (if possibly tedious–though, if you know shell scripting a little bit, you can automate it all away with a few lines).

I suspect the easiest thing to do, if you’re coming from a Virtualmin Professional system would be to ask Virtualmin about the users using its command line tools (which can produce text in a format that’s easy to script with, or dump into a file, or whatever). Unfortunately, Virtualmin GPL doesn’t have the list-users command. In Professional you could do:

virtualmin list-users –all-domains

And that would list all of the Virtualmin-managed mail users on the system. Adding the –multiline option would list it in a more scriptable/parseable style. If cPanel has a bulk import feature, I’m sure the list could be massaged into a format it would accept.

Once the mailboxes were created, you’d then need to move the mail over…which could probably be done with a script that just checks the home directory of the user on the source system and puts it into the home directory on the destination system, using ssh/scp (/etc/passwd has the users home directory info).

Mind if I ask why you’re moving from Virtualmin to cPanel?

Oh, yeah, I forgot to mention that if cPanel mail users have actual user accounts (I’m not sure…they could also be in some sort of dedicated database, which would mean this suggestion won’t work), you could also copy the encrypted passwords from the users on the Virtualmin system directly into the shadow file on the cPanel system. Presumably everybody is using the same password crypting function for users, since it’s a function of the OS rather than the control panel.

Hi Joe, thanks for your advice. I’m not sure if I have the luxury of Virtualmin Pro, I’ll have to look into that. And, to answer your question, the reason I’m moving from Virtualmin to cPanel is simply because I’m moving from one hosting company to another; the old provider was using Virtualmin and the new one is using cPanel. It’s not a matter of choosing one over the other, just a case of using what’s being offered! So thanks for your advice, I’ll look into it and see how it goes…