How to migrate mail from one user to another?

[matrixes]

I'm at at a point where I need to consolidate/merge accounts for closure, as they have ballooned a bit too much.

I can't find any instructions on ow or whether it's even possible to merge accounts efficiently. I've more or less concluded that I will have to forward all emails from one account to another.

Is there another way to make this task less arduous? I need to merge the emails in order to be able to access them from the account(s) I'm merging to.

The whole point of this is to use fewer actual atomic accounts for communication, and still have access to the emails sent to the accounts I'm merging from, without having to login to said accounts.

[casperklein]

docker-mailserver/compose.yaml

Lines 16 to 17 in 3faa40b

	volumes:
	- ./docker-data/dms/mail-data/:/var/mail/

Just copy the files from

./docker-data/dms/mail-data/example.com/postmaster/cur/

to

./docker-data/dms/mail-data/new-example.com/postmaster/cur/

[matrixes]

Worked very well!

[polarathene]

Moving the mail content like answered already should work. The mail will still have the old recipient address it was delivered to, but that shouldn't be an issue AFAIK.

The whole point of this is to use fewer actual atomic accounts for communication, and still have access to the emails sent to the accounts I'm merging from, without having to login to said accounts.

Just in case these options weren't obvious going forward:

• Virtual aliases (setup alias add ...) are great for multiple addresses to a single mailbox.
• Sub-addresssing / Plus Addressing, is similar but has no specific aliases, allowing whatever suffix after the + in the local-part of the address to route to the same mailbox. You can pair that with Dovecot Sieve to recognize specific tags to store into different folders in your mailbox for organization automatically.

Those doc links for sub-addressing are presently only available / rewritten on :edge docs, so you might not have seen them covered well until the DMS v15 release. I revised that topic vs the current latest and v14 docs, so it should be much more easier to grok, if not let me know any feedback so I can improve it 👍

[matrixes]

Thanks for the tips!

I went into aliasing a bit too late, which led to this situation.

My goal has always been to keep the number of accounts low but I couldn't figure out how to send emails through my catchall address with a custom sender address, so I saw few other options other than creating accounts.

My ideal situation would be something along the lines of

• Use a catchall to receive all emails
• Use custom sender addresses for certain recipients (friends, banks, etc)

I'm not really sure how to solve this smoothly though. I'd have to look into whether an alias can be allowed to send emails through my catchall-account...

[polarathene]

If you view the edge docs on the account management pages, these have been rewritten for upcoming v15 of DMS docs. They better document what you can do and any caveats to be aware of.

Roughly, aliases will create dummy accounts that can be used to login with but this is more of an unintended side-effect of a workaround to support Dovecot Quotas properly. Any actual mailbox account you can login in with can send as any sender address (provided you don't set SPOOF_PROTECTION=1).

Using a catch-all alias will have precedence over real mailbox accounts due to Postfix resolving aliases first, and presently DMS doesn't allow you to have an alias with the same address as a real mailbox account. You'll find there is an open issue about a manual workaround for such, the docs I mention should have a link to that should you need it.

Sub-addressing only works for receiving mail, you can't use it for a sender address IIRC. It still serves the purpose of signing up to services with a tag like [email protected], and using sieve script to deliver to a bank folder in your mailbox.

If your subaddress gets leaked/sold somewhere, you'd then know which service did so if the unrelated sender is automating such mail without any stripping the tag. Aliases may work better here as they can't be stripped away (you can still use the sieve scripts for sorting IIRC, but this requires some undocumented config changes AFAIK), aliases can be used as a sender address but Postfix may resolve them once sending in which case the reply address may differ from what you intended 🤔

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Is there any reason you'd want a catch-all vs rejecting mail that doesn't have a valid address?