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<p>Hello;</p>
<p>We were able to set up shared folders in a cluster (using dovecot
as proxy on dedicated front-end servers, without using director)
by following
<a class="moz-txt-link-freetext"
href="https://doc.dovecot.org/configuration_manual/shared_mailboxes/cluster_setup/">https://doc.dovecot.org/configuration_manual/shared_mailboxes/cluster_setup/</a>.<br>
</p>
<p>Here is our related conf on imap farms (dovecot v2.3.16 on
Almalinux):</p>
namespaces:
<pre>mail_location = maildir:~/Maildir
namespace default {
inbox = yes
location =
prefix =
separator = /
}</pre>
<pre>namespace shared {
list = children
location = imapc:~/shared/%%u:INDEXPVT=~/shared-pvt/%%u
prefix = shared/%%u/
separator = /
subscriptions = no
type = shared
}
</pre>
imapc settings:<br>
<pre>imapc_features = fetch-bodystructure fetch-headers rfc822.size search modseq acl delay-login
imapc_host = XXXXXX
imapc_master_user = %{user}
imapc_password = XXXXXX
imapc_port = XXXXXX</pre>
<pre>passdb {
args = password=#hidden_use-P_to_show# userdb_namespace/shared/disabled=yes userdb_acl_user=%{auth_user} allow_nets=XXXXX/XX
driver = static
master = yes
}
dict {
acl-mysql = mysql:/etc/dovecot/conf.d/dovecot-dict-sql.conf.ext
}
</pre>
This way, a folder is created under ~/ : shared & shared-pvt :<br>
<br>
When user A shares a folder with B, B will find
~/shared/userA/sharedfolder<br>
<br>
I should mention that the user authentication (backend: mysql) uses
the full email address as we are in a multi-tenant context.<br>
<br>
So the folder looks like ~/shared/usera@domain.tld/folder<br>
<br>
Since then, everything works perfectly, we can share and see the
shared folders in the webmail (SOGo).<br>
<br>
Unfortunately, accessing these folders through an imap client
(tested on Thunderbird and MSOutlook) is impossible because the
subscription fails (the folder is listed, but the subscription
doesn't seem to do anything).<br>
I could not find any relevant logs but I was able to confirm on the
command line: I am able to view folder with LIST, subscribe with an
"OK" output, but the folder is not listed with LSUB.<br>
<br>
So I could see that the subscribtion file in maildir shows incorrect
entries:
<pre>V 2
Sent
Trash
Drafts
Junk
shared/testuser1@sub domain tld/INBOX/folder</pre>
The dots in the folder names are replaced by tabs.<br>
<br>
I was able to recover things by editing the file as follows:
<pre>Sent
Trash
Drafts
Junk
<a class="moz-txt-link-abbreviated moz-txt-link-freetext" href="mailto:shared/testuser1@sub.domain.tld/INBOX/folder">shared/testuser1@sub.domain.tld/INBOX/folder</a></pre>
<br>
This means that Maildir++ and V2 subscription can't handle dots in
folders.<br>
<br>
I found a previous discussion: <a class="moz-txt-link-freetext"
href="https://dovecot.org/pipermail/dovecot/2021-January/121233.html">https://dovecot.org/pipermail/dovecot/2021-January/121233.html</a><br>
But the final advice can't be applied on our side:<br>
- changing LAYOUT to FS is not possible for us<br>
- we have already migrated the dot separator to slash<br>
- changing the layout only for shared namespaces does not solve the
problem and totally breaks the access to shared folders.
<p>Thanks a lot for your advice</p>
<p>Best regards</p>
<p>Julien<br>
</p>
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