Hi!
With Dovecot Director and Proxy or the new (great!) TAG-feature from Dovecot it's easy to set up a shared IMAP-Cluster with individual local filesystems.
But I'm unsure if it's possible to build a setup where shared mailboxes still can work.
If user A is on Cluster (1) and user B is on (2), and Cluster (1) does not have access to the mail-home from B on (2),
then user A can not reach the shared folders provided from User B on (2).
I hope that there is a kind of backend-proxy-mechanism, so that the imap process of A on (1) can imap-proxy the requests for the shared folder to a node from cluster shard (2).
And: To be exact, the imap process on (1) should forward the request to cluster (2) by the director system to make sure, that the connection will terminate on the right active backend of User B.
This sounds like a special problem if local filesystems with mdbox are used and I now the great features of using Dovecot on Object Store, where every node can check out all mail-locations from all users.
But especially on obox-systems it is very important that requests for a user are always terminated on the same backend. So how can shared folders work there?! Node (1) can not checkout the shared folders from User B if his obox storage is already active on another host (2)!
Peer
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