I’m planning to migrate my email to a different provider, but they don’t give much storage, so I was wondering what people would recommend for this kind of setup: basically I’d like to use the new provider as something like a relay. I’d want them to only store an email or two at a time and have some kind of self hosted solution that just grabs the emails from the provider and stores them after deleting them off the provider so it’s never storing my entire email history, and also keeps my sent emails somewhere so that I have a copy of it. Ideally I’d wanna be able to set this up with a mail client like NextCloud’s.
The good old fetchmail is probably what you’re looking for. Run your local/self-hosted email server and then use fetchmail as described here to fetch the email from the email provider and deliver into the local accounts. You also have getmail (does the same but is written in python), guide here, or go-getmail …
Alternatively, and probably way better:
Postfix has a feature called ETRN service, documented here. It can be used to incoming emails queued deliver it to another server when a connection is available:
From what I know about it you might be able to:
relay_domains
here and here.nc -c 'echo "ehlo selfhosted.example.org";sleep 1;echo "etrn your-domain.example.org";sleep 1;echo "quit"' remote-cloud-server.example.org 25
This command will connect to the cloud server and ask it to deliver all queued email to the self-hosted instance. This can be setup to run every x minutes, or if you want to get fancy, when the network goes up with the
network-online.target
target like described here. Note that the script isn’t strictly necessary, is just guarantees that if the connection between servers goes down when it comes back you’ll get all the queued email delivered right away.The following links may also be of interest so your local / self-hosted email server can send email:
Now a note about NextCloud: their webmail is the worst possible solution, I wrote very detailed description of the issues here. Do yourself a favor and use Roundcube.
Agree about the Nextcloud client, but it’s easy enough to replace it with the SnappyMail plug in which works a treat.