Is it possible to use Nextcloud's main storage on the host?

I want to put my Maildir into Nextcloud, and have my Nextcloud host fetch and index new mail.

Is it possible to do this without running a Nextcloud client on the host machine? I have mail archives going back to the early 2000s totaling around 15gb. My Nextcloud host is small, so avoiding doubling the storage like this would be a big win.

I know where it stores all the files, but everything is owned by www-data, which complicates things a bit.

You can use External storage support for this.

Just to make sure I understand the suggestion, you’re saying I keep my email in ~/Maildir, and use external storage with the local backend to access that from Nextcloud?

I suppose that works, but it seems likely that one of two undesirable things would occur:

  • My mail wouldn’t get backed up with the rest of my Nextcloud data, or
  • Nextcloud would pull files from ~/Maildir into its storage, which has the issue with doubling required storage.

I think my best bet might be to use a FUSE webdav mount to access the data.

I use External storage for other purpose. Just want to share that it won’t do an extra backup that double the storage usage. Your case should be triggered by some other settings you did before.

Yes, you understood me correctly, but let me explain something for to be sure:

  1. as @vvong said it will not double the storage usage
  2. it will appear as external storage in your client just check it for syncing%D0%90%D0%BD%D0%BD%D0%BE%D1%82%D0%B0%D1%86%D0%B8%D1%8F
  3. no reason for webdav if your folder is local on same host