So once I’ve installed a Postfix/Dovecot/Roundcube mail server, another problem presents itself.
I have a LOT of emails on my old GroupWise Server that I can’t afford to lose. Does anyone have any idea how to transfer mails from one mail server to a new one?
I’ve used imapsync many times to do that. I use cyrus imap, but I see no reason it should not work just as well for a dovecote server.
Emmett
Yes imapsync is great
The question is, can I do this internally? I only have one MX record.
Yes you can, imapsync uses IMAP so ports 143 or 993 depending on whether you have SSL enabled for IMAP. It syncs the mailboxes from the old server to the new one.
You will however have to create the new mailboxes first as for the imapsync you provide the old mailbox login and password, and the new mailbox login and password on the new server so that the emails get copied across.
The MX record is irrevelant at this point, since you are not sending/receiving emails. That said, I would ensure that the MX record doesn’t point at the old server otherwise after sync you might find new emails have arrived on the old server, and then it would require re-running imapsync for all logins to ensure no emails were lost. Of course, if you redirect the MX record to the new server, make sure all email accounts exist on the new one, so that when emails come in they are not rejected else you will lose them that way as well.
The sync can be done using the internal IP address, no need to use the public one.
imapsync exists in the epel repository so as long as you have this enabled you can install it easy enough.
I have an interesting question.
Using Postfix, Dovecot, Roundcube., Let us say I send a 10MB video clips as attachments to 20 of my friends. Are 20 emails stored in Sent with 20 attachments or are 20 emails stored and only ONE attachment?
If you sent a single email to 20 recipients, then it’s one email and one attachment. If you sent 20 individual emails to each person, then there will be 20 emails + 20 attachments.
That said, if a distro has the ability to use eg: btrfs as the filesystem underneath, there is de-duplication functionality in btrfs, which means that those 20 files all being the same, would only use up the space of 1 attachment. Although this doesn’t apply in your situation since btrfs isn’t in the repositories.
That’s always been one of the things I like the most about GroupWise. (a) no one ever hacked it and (b) It will save ONE copy of the attachment, even if there are 1,000 emails. It just keeps a pointer to the attachment in each mail on the server.
Then you are lucky since: Novell Groupwise : List of security vulnerabilities shows an absolute ton of vulnerabilities for GroupWise, and quite a lot of critical (red) ones on there for GroupWise 8 and older. Not also including the fact it probably doesn’t even support TLS 1.2 or higher to mitigate older SSL/TLS problems with SSLv2, SSLv3, TLSv1.0, etc.
Certainly something to definitely migrate away from considering it’s no longer fixed to get rid of all those critical issues.
Exactly what I’m trying to do. It’s a big change - takes time and I’m no Linux Guru, as you know.
I used to have my mail server on Gentoo Linux around 2006 - 2007 and managed to migrate it to Zimbra and was using Zimbra from around v6 to v8.8.15, and then during the last 1-2 years migrated that to Zoho Mail instead. Zoho Mail is actually pretty good, 1 euro per email account with 10GB storage, and then configure it up with all the functionality needed like DKIM, SPF, DMARC, etc. Don’t have to worry about upgrading the VPS that the Mail Server sit’s on, and I just use it. I guess I got a bit lazy 
Please tell us your GroupWise server is backed up to multiple places. If these emails are truly critical, you need at least two backups. (Since the power can glitch while making a backup and burn both the original and the current backup.)
After close to 40 years in computers. I think I’m well aware of these facts.
Just to clarify on this GroupWise is still available and maintained/fixed. It’s now owned by Microfocus with the latest release (2018.4.1) being just over two months ago.
M
Correct, although my reply was in response to the OP which is running a very old Groupwise 7/8 which is no longer supported and which is why he is migrating away from it. This was why I provided the link to the CVE’s so the risk severity could be seen for running an older version - and hence my comment about migrating away from something that is no longer fixed.
Had the OP been using the latest and greatest it wouldn’t necessarily be too much of an issue as such.
Hi Ian,
I must have missed where he said what version of GW the OP was migrating from, I only saw “old” which can cover a multitude of sins including the-system-we’re-getting-rid-of
Mark.