Another item.

Again, it may be a 2.3.13 issue and I'm now on 2.3.17. But...I had problem when using the "-N" parameter for dsync. So - I just have (had):

replication_dsync_parameters = -d -l 30 -U -x INBOX/virtual -x INBOX/shared

Now that things are working - I wanted to have my other namespaces sync as well. So I went to:

replication_dsync_parameters = -d -l 30 -U -n INBOX -n INBOX/Archives -n INBOX/Lists -x INBOX/virtual -x INBOX/shared

This appears to be working (the sync is just starting)...but I'm seeing lock errors in the logs such as: Dec 3 14:34:24 bubba dovecot: doveadm(dmiller@amfes.com)<31785>: Error: Couldn't lock /var/mail/amfes.com/dmiller/.dovecot-sync.lock: fcntl(/var/mail/amfes.com/dmiller/.dovecot-sync.lock, write-lock, F_SETLKW) locking failed: Timed out after 30 seconds (WRITE lock held by pid 31373)

Checking the pid in question I see it's actively syncing a folder in my mailbox. So I'm guessing, purely guessing, that by having multiple namespaces explicitly directed to sync Dovecot is trying to start a sync process for each of those namespaces - but all of them share a common lock and therefore only one operation is allowed at a time.

Am I correct, and whether or not I am - how can I correct these errors? Do I dare try going back to just "-N"?

-- Daniel

------ Original Message ------ From: "Daniel Miller" dmiller@amfes.com To: dovecot@dovecot.org Sent: 12/3/2021 2:16:28 PM Subject: Replication weirdness

First, I have to say this. After configuring everything correctly - and that means *everything* correctly - Dovecot replication Just Works. I'm not sure how (yes I do - Timo & Co. Magic) - but it does. Real-time new sync is near instantaneous.

Now the problem. Or the background for the problem. My primary server uses sdbox for primary storage, mdbox for archival storage, and fts-solr. I spun up a second server, using sdbox, mdbox, and fts-flatcurve. My namespaces are as defined below. As best I can tell (based on diff comparing two 'doveconf -n' outputs) my namespaces are the same on both servers.

namespace archives { list = children location = mdbox:/var/mail/%d/%n/Archives/mdbox mailbox Unsorted { auto = no special_use = \Archive } prefix = INBOX/Archives/ separator = / subscriptions = no type = private } namespace inbox { alias_for = hidden = no inbox = yes list = yes location = mailbox "Deleted Messages" { auto = no autoexpunge = 30 days special_use = \Trash } mailbox Drafts { auto = subscribe special_use = \Drafts } mailbox Sent { auto = subscribe special_use = \Sent } mailbox Trash { auto = subscribe autoexpunge = 30 days special_use = \Trash } prefix = INBOX/ separator = / subscriptions = no type = private } namespace lists { list = children location = mdbox:/var/mail/%d/%n/Lists/mdbox prefix = INBOX/Lists/ separator = / subscriptions = no type = private } namespace subscriptions { hidden = yes list = no location = prefix = separator = / subscriptions = yes type = private } namespace usershares { list = yes location = sdbox:/var/mail/%%d/%%n/sdbox:NO-NOSELECT prefix = INBOX/shared/%%d/%%n/ separator = / subscriptions = no type = shared } namespace virtual { list = children location = virtual:/var/mail/%d/%n/virtual mailbox Flagged { comment = All my flagged messages special_use = \Flagged } prefix = INBOX/virtual/ separator = / subscriptions = no }

I also have: plugin { mailbox_alias_new = Sent Messages mailbox_alias_new2 = Sent Items mailbox_alias_new3 = Deleted Messages mailbox_alias_old = Sent mailbox_alias_old2 = Sent mailbox_alias_old3 = Trash }

This setup worked fine with my single server. Then I enabled replication - just on the primary. Dsync went to work (it seemed to take forever for the initial sync but that's what happens with large mailboxes and slow internet connections).

The problem came up with certain subfolders. And I believe it only happens with subfolders that have spaces in their names. I had two user's mailboxes (under Sent), one of which had a "Sent Messages" symlink alias for "Sent", that started generating tens or hundreds of duplicates during sync. Fortunately those subfolders only had a few mails in them. But I had trees looking like:

[...] (below is under /var/mail/domain/user/sdbox/mailboxes/Sent/) Proposal Requests-temp-c6e003375e64a961c93d00009db5accb-temp-1-temp-f80b1a00ce9aa961a86-temp-2 Proposal Requests-temp-c6e003375e64a961c93d00009db5accb-temp-1-temp-f80b1a00ce9aa961a86-temp-3 Proposal Requests-temp-c6e003375e64a961c93d00009db5accb-temp-2-temp-023fa4271c9ca9611ade0400b88bfabe Proposal Requests-temp-c6e003375e64a961c93d00009db5accb-temp-2-temp-023fa4271c9ca9611ad-temp-1 Proposal Requests-temp-c6e003375e64a961c93d00009db5accb-temp-2-temp-1 Proposal Requests-temp-c6e003375e64a961c93d00009db5accb-temp-2-temp-2 Proposal Requests-temp-c6e003375e64a961c93d00009db5accb-temp-2-temp-2-temp-1-temp-1 Proposal Requests-temp-c6e003375e64a961c93d00009db5accb-temp-2-temp-3 Proposal Requests-temp-c6e003375e64a961c93d00009db5accb-temp-2-temp-4 Proposal Requests-temp-c6e003375e64a961c93d00009db5accb-temp-2-temp-5 Proposal Requests-temp-c6e003375e64a961c93d00009db5accb-temp-2-temp-e2aa0f35c99ba961356500009db5accb [...]

I kept stopping, cleaning up the folders, and re-starting - and they kept regenerating. I tried renaming the folders to eliminate the spaces and I think that helped in one case - for the others I just moved the folders outside of the mail area completely to let the sync finish.

Now that it's been stable for a day or two - I enabled sync in the other direction. And after setting *all* the required parameters instead of just most of them...it's working. But...I'm nervous about moving the problem folders back over. I will say, if it makes any difference, my primary server *was* running version 2.3.13 and I just updated it to 2.3.17. The remote is also 2.3.17.

-- Daniel