November 2025 - dovecot

"Mailbox attribute iteration failed": error running doveadm sync
by jamie＠mayfirst.org 15 Nov '25

15 Nov '25

I'm running doveadm sync to sync a remote mailbox over ssh (the remote server is running 2.3.13) with a local mailbox (the local server is running 2.4.1). I get the following errors: Error: brain M: Exporting mailbox INBOX failed: Mailbox attribute iteration failed: Internal error occurred. Refer to server log for more information. [2025-11-15 19:25:32] Error: cmd sync: Remote command returned error 75: ssh root(a)mailstore002.mayfirst.org doveadm dsync-server -u jamie-test dsync-server Does anyone have suggestions on how to fix? Also, any tips on how to increase logging verbosity would be great - I'm not getting anything in the logs. Here is the full transcript of the errors. Thanks for any suggestions! jamie Debug: Loading modules from directory: /usr/lib/dovecot/modules/doveadm Debug: Skipping module doveadm_acl_plugin, because dlopen() failed: /usr/lib/dovecot/modules/doveadm/lib10_doveadm_acl_plugin.so: undefined symbol: acl_user_module (this is usually intentional, so just ignore this message) Debug: Skipping module doveadm_quota_plugin, because dlopen() failed: /usr/lib/dovecot/modules/doveadm/lib10_doveadm_quota_plugin.so: undefined symbol: quota_user_module (this is usually intentional, so just ignore this message) Debug: Module loaded: /usr/lib/dovecot/modules/doveadm/lib10_doveadm_sieve_plugin.so Debug: Skipping module doveadm_fts_plugin, because dlopen() failed: /usr/lib/dovecot/modules/doveadm/lib20_doveadm_fts_plugin.so: undefined symbol: fts_backend_rescan (this is usually intentional, so just ignore this message) Debug: Skipping module doveadm_fts_flatcurve_plugin, because dlopen() failed: /usr/lib/dovecot/modules/doveadm/libdoveadm_fts_flatcurve_plugin.so: undefined symbol: fts_flatcurve_user_module (this is usually intentional, so just ignore this message) Debug: Skipping module doveadm_mail_crypt_plugin, because dlopen() failed: /usr/lib/dovecot/modules/doveadm/libdoveadm_mail_crypt_plugin.so: undefined symbol: crypt_acl_setting_parser_info (this is usually intentional, so just ignore this message) Nov 15 19:28:47 Debug: Loading modules from directory: /usr/lib/dovecot/modules/doveadm Nov 15 19:28:47 Debug: Skipping module doveadm_acl_plugin, because dlopen() failed: /usr/lib/dovecot/modules/doveadm/lib10_doveadm_acl_plugin.so: undefined symbol: acl_user_module (this is usually intentional, so just ignore this message) Nov 15 19:28:47 Debug: Skipping module doveadm_quota_plugin, because dlopen() failed: /usr/lib/dovecot/modules/doveadm/lib10_doveadm_quota_plugin.so: undefined symbol: quota_user_module (this is usually intentional, so just ignore this message) Nov 15 19:28:47 Debug: Skipping module doveadm_fts_plugin, because dlopen() failed: /usr/lib/dovecot/modules/doveadm/lib20_doveadm_fts_plugin.so: undefined symbol: fts_backend_rescan (this is usually intentional, so just ignore this message) Nov 15 19:28:47 Debug: Skipping module doveadm_fts_flatcurve_plugin, because dlopen() failed: /usr/lib/dovecot/modules/doveadm/libdoveadm_fts_flatcurve_plugin.so: undefined symbol: fts_flatcurve_user_module (this is usually intentional, so just ignore this message) Nov 15 19:28:47 Debug: Skipping module doveadm_mail_crypt_plugin, because dlopen() failed: /usr/lib/dovecot/modules/doveadm/libdoveadm_mail_crypt_plugin.so: undefined symbol: crypt_acl_setting_parser_info (this is usually intentional, so just ignore this message) Nov 15 19:28:47 doveadm(jamie-test)<46454><>: Debug: auth-master: userdb lookup(jamie-test): Started userdb lookup Nov 15 19:28:47 doveadm(jamie-test)<46454><>: Debug: auth-master: conn unix:/run/dovecot/auth-userdb: Connecting Nov 15 19:28:47 doveadm(jamie-test)<46454><>: Debug: auth-master: conn unix:/run/dovecot/auth-userdb (pid=43923,uid=0): Client connected (fd=9) Nov 15 19:28:47 doveadm(jamie-test)<46454><>: Debug: auth-master: conn unix:/run/dovecot/auth-userdb (pid=43923,uid=0): auth input: jamie-test system_groups_user=jamie-test uid=1002 home=/home/users/jamie-test gid=100 Nov 15 19:28:47 doveadm(jamie-test)<46454><>: Debug: auth-master: userdb lookup(jamie-test): auth USER input: jamie-test system_groups_user=jamie-test uid=1002 home=/home/users/jamie-test gid=100 Nov 15 19:28:47 doveadm(jamie-test)<46454><>: Debug: auth-master: userdb lookup(jamie-test): Finished userdb lookup (username=jamie-test system_groups_user=jamie-test uid=1002 home=/home/users/jamie-test gid=100) Nov 15 19:28:47 doveadm(jamie-test): Debug: Effective uid=1002, gid=100, home=/home/users/jamie-test Nov 15 19:28:47 doveadm(jamie-test): Debug: open(/proc/self/io) failed: Permission denied (euid=1002(jamie-test) egid=100(users) missing +r perm: /proc/self/io) Nov 15 19:28:47 doveadm(jamie-test): Debug: Namespace inbox: type=private, prefix=INBOX., sep=., inbox=yes, hidden=no, list=yes, subscriptions=yes Nov 15 19:28:47 doveadm(jamie-test): Debug: maildir++: root=/home/users/jamie-test/Maildir, index=, indexpvt=, control=, inbox=/home/users/jamie-test/Maildir, alt= Nov 15 19:28:47 doveadm(jamie-test): Debug: Namespace : type=private, prefix=, sep=, inbox=no, hidden=yes, list=no, subscriptions=no Nov 15 19:28:47 doveadm(jamie-test): Debug: none: root=/home/users/jamie-test/Maildir, index=, indexpvt=, control=, inbox=/home/users/jamie-test/Maildir, alt= Nov 15 19:28:47 doveadm(jamie-test): Debug: brain M: Namespace inbox has path /home/users/jamie-test/Maildir Nov 15 19:28:47 doveadm(jamie-test): Debug: Mailbox INBOX: Mailbox opened Nov 15 19:28:47 doveadm(jamie-test): Debug: Mailbox INBOX: Mailbox opened Nov 15 19:28:47 doveadm(jamie-test): Debug: Namespace inbox: Using permissions from /home/users/jamie-test/Maildir: mode=0700 gid=default Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Local mailbox tree: INBOX guid=c06cb11ffc3b2e667cee07009334e653 uid_validity=1669914524 uid_next=1 subs=no last_change=0 last_subs=0 Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Local mailbox tree: INBOX.Spam guid=00000000000000000000000000000000 uid_validity=0 uid_next=0 subs=yes last_change=0 last_subs=1763215050 Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Local mailbox tree: INBOX.Sent guid=00000000000000000000000000000000 uid_validity=0 uid_next=0 subs=yes last_change=0 last_subs=1763215050 Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Local mailbox tree: INBOX.Archive guid=e42d3631a91ba85ef96f00000df6ea83 uid_validity=1586118770 uid_next=1 subs=yes last_change=0 last_subs=1763215050 Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Local mailbox tree: INBOX.Archives guid=693e80288e6e8b5e153300000df6ea83 uid_validity=1586118767 uid_next=1 subs=no last_change=0 last_subs=0 Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Local mailbox tree: INBOX.Drafts guid=60042a30bf3e5e64d44f15001890bc3b uid_validity=1669914525 uid_next=1 subs=yes last_change=0 last_subs=1763215050 Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Local mailbox tree: INBOX.Junk guid=387dc412e591b0683b3b34009334e653 uid_validity=1714306055 uid_next=1 subs=yes last_change=0 last_subs=1763215050 Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Local mailbox tree: INBOX.Keep Forever guid=99b2cc1be0826d61f07e00000df6ea83 uid_validity=1586118773 uid_next=1 subs=yes last_change=0 last_subs=1763215050 Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Local mailbox tree: INBOX.Trash guid=a8494334bf3e5e64d44f15001890bc3b uid_validity=1669914528 uid_next=1 subs=yes last_change=0 last_subs=1763215050 Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Remote mailbox tree: INBOX guid=c06cb11ffc3b2e667cee07009334e653 uid_validity=1669914524 uid_next=561 subs=no last_change=0 last_subs=0 Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Remote mailbox tree: INBOX.Spam guid=00000000000000000000000000000000 uid_validity=0 uid_next=0 subs=yes last_change=0 last_subs=1683898047 Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Remote mailbox tree: INBOX.Sent guid=00000000000000000000000000000000 uid_validity=0 uid_next=0 subs=yes last_change=0 last_subs=1683898047 Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Remote mailbox tree: INBOX.Drafts guid=60042a30bf3e5e64d44f15001890bc3b uid_validity=1669914525 uid_next=1 subs=yes last_change=0 last_subs=1683898047 Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Remote mailbox tree: INBOX.Trash guid=a8494334bf3e5e64d44f15001890bc3b uid_validity=1669914528 uid_next=1 subs=yes last_change=0 last_subs=1683898047 Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Remote mailbox tree: INBOX.Archive guid=e42d3631a91ba85ef96f00000df6ea83 uid_validity=1586118770 uid_next=1 subs=yes last_change=0 last_subs=1763213508 Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Remote mailbox tree: INBOX.Archives guid=693e80288e6e8b5e153300000df6ea83 uid_validity=1586118767 uid_next=1 subs=no last_change=0 last_subs=0 Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Remote mailbox tree: INBOX.Junk guid=387dc412e591b0683b3b34009334e653 uid_validity=1714306055 uid_next=1 subs=yes last_change=0 last_subs=1763213508 Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Remote mailbox tree: INBOX.Keep Forever guid=99b2cc1be0826d61f07e00000df6ea83 uid_validity=1586118773 uid_next=1 subs=yes last_change=0 last_subs=1763213508 Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Remote mailbox tree deletion: guid=dcb7483819278b5e7a5a00000df6ea83 type=mailbox timestamp=1763214618 name= local update=not found Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Remote mailbox tree deletion: guid=e05fa533bf3e5e64d44f15001890bc3b type=mailbox timestamp=1763214618 name= local update=not found Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Remote mailbox tree deletion: guid=c30776db7d3c7eaa71cdf47ee8a11926 type=dir timestamp=1763214618 name=INBOX.Sent local update=marked as deleted Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Remote mailbox tree deletion: guid=edfa9436de94e7fff67418728a00db1d type=dir timestamp=1763214618 name=INBOX.Spam local update=marked as deleted Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Mailbox INBOX: local=c06cb11ffc3b2e667cee07009334e653/0/1, remote=c06cb11ffc3b2e667cee07009334e653/0/1: Mailboxes are equal Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Mailbox INBOX.Archive: local=e42d3631a91ba85ef96f00000df6ea83/0/1, remote=e42d3631a91ba85ef96f00000df6ea83/0/1: Mailboxes are equal Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Mailbox INBOX.Archives: local=693e80288e6e8b5e153300000df6ea83/0/1, remote=693e80288e6e8b5e153300000df6ea83/0/1: Mailboxes are equal Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Mailbox INBOX.Drafts: local=60042a30bf3e5e64d44f15001890bc3b/0/1, remote=60042a30bf3e5e64d44f15001890bc3b/0/1: Mailboxes are equal Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Mailbox INBOX.Junk: local=387dc412e591b0683b3b34009334e653/0/1, remote=387dc412e591b0683b3b34009334e653/0/1: Mailboxes are equal Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Mailbox INBOX.Keep Forever: local=99b2cc1be0826d61f07e00000df6ea83/0/1, remote=99b2cc1be0826d61f07e00000df6ea83/0/1: Mailboxes are equal Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Mailbox INBOX.Sent: local=00000000000000000000000000000000/0/0, remote=00000000000000000000000000000000/0/2: Directory rename branch not found Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Mailbox INBOX.Spam: local=00000000000000000000000000000000/0/0, remote=00000000000000000000000000000000/0/2: Directory rename branch not found Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Mailbox INBOX.Trash: local=a8494334bf3e5e64d44f15001890bc3b/0/1, remote=a8494334bf3e5e64d44f15001890bc3b/0/1: Mailboxes are equal Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: Mailbox INBOX: Mailbox opened Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Syncing mailbox c06cb11ffc3b2e667cee07009334e653: UIDNEXT changed: 1 -> 561 Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: doveadm-sieve: Iterating Sieve mailbox attributes Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: sieve: Pigeonhole version 2.4.1-4 (0a86619f) initializing Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: sieve: storage personal: file: Storage path '/home/users/%u/.sieve' not found Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: sieve: storage personal: file: Failed to normalize active script directory (path=/home/users/%u): Part of the path does not exist (yet) Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: sieve: storage personal: file: Using active Sieve script path: /home/users/%u/.dovecot.sieve Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: sieve: storage personal: file: Using script storage path: /home/users/%u/.sieve Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: sieve: storage personal: file: Using permissions from defaults: mode=0700 gid=-1 Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Error: brain M: Exporting mailbox INBOX failed: Mailbox attribute iteration failed: Internal error occurred. Refer to server log for more information. [2025-11-15 19:28:47] Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: brain M: Import mailbox INBOX: Saved UIDs: Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Error: cmd sync: Remote command returned error 75: ssh root(a)mailstore002.mayfirst.org doveadm dsync-server -u jamie-test dsync-server Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: User session is finished Nov 15 19:28:47 dsync-local(jamie-test)<esqfB2/UGGl2tQAAVqcyLg>: Debug: auth-master: conn unix:/run/dovecot/auth-userdb (pid=43923,uid=0): Disconnected: Connection closed (fd=9)

1 0

doveadm -A finds non existent users
by Kippels, Julian 14 Nov '25

14 Nov '25

Hi, I am trying to iterate through all users using "doveadm sieve list -A" and I am seeing a lot of messages like this one: doveadm(someuser): Info: User no longer exists, skipping When I do "doveadm sieve list -u someuser" I get the following: doveadm(someuser): Error: User doesn't exist I have defined LDAP as my userdb and "someuser" is not present in the LDAP anymore. Where does doveadm -A get this user from and how can I clean this up? Thanks Julian

3 3

multiple passdbs on 2.4.1
by Lou Duchez 13 Nov '25

13 Nov '25

I recently upgraded from 2.3 to 2.4.1, a little unwillingly (thanks Fedora), and I've almost got 2.4.1 working on my failover mail server. The failover server's job is, if the main mail server is inaccessible, mail gets delivered to the failover instead. Then the main server will retrieve mail from the failover server when it can. This has worked very well for many years. The way I implemented it was, I had two passdb's on the failover server: one for ordinary users who might need to access the failover server directly (login and password required), and one so that the main mail server could grab mail from the failover server (no password required). This broke when I went to 2.4.1; now, no matter what I do, Dovecot honors only one of the passdbs. Here is the configuration as it stands now. The intention is that, if the user properly authenticates with the first passdb, they're authenticated and the second passdb isn't consulted. But if the user doesn't authenticate with the first passdb, Dovecot moves on to the second passdb. # the passdb for normal users to check their mail on the failover server passdb passwd-file { passwd_file_path = /vmail/Maildir/passwdfile passdb_result_success = return-ok passdb_result_failure = continue-fail } # the passdb for the main server to grab mail from the failover server passdb passwd-file { passwd_file_path = /vmail/Maildir/passwdfile passdb_skip = authenticated fields { nopassword = yes allow_nets = xxx.xxx.xxx.xxx/32 } passdb_result_success = return-ok passdb_result_failure = return-fail } As things stand now, Dovecot always moves on to the second passdb and authenticates the user, or not, according to the outcome of the second passdb. The outcome of the first passdb does not seem to matter. Curiously, if I comment out the second passdb, the first passdb authenticates users as expected. I've tried all kinds of gyrations with passdb_result_success and passdb_result_failure, and none of them seem to work. The options I have there right now are, to the best of my knowledge, the ones that best match the flow I want to be seeing. There's a chance there's a bug in 2.4.1, but I bet I'm doing something wrong. What am I doing wrong?

3 6

authentication back-ends - go to specific one?
by lejeczek 13 Nov '25

13 Nov '25

Hi guys. Is it possible to tell *dovecot* to authenticate with a specific back-end for a given domain? If it would not the only back-end a given account of a specific domain would try, then it would be the first back-end such account would try to auth against - possible? many thanks, L. Hi guys. Is it possible to tell dovecot to authenticate with a specific back-end for a given domain? If it would not the only back-end a given account of a specific domain would try, then it would be the first back-end such account would try to auth against - possible? many thanks, L.

2 1

after upgrade to 2.4 I get passwd-file: Password mismatch
by Helmut K. C. Tessarek 11 Nov '25

11 Nov '25

I upgraded dovecot from 2.3 to 2.4 today and all of a sudden I get an authentication error: passwd-file: Password mismatch My config looks like this: passdb pam { driver = pam } passdb passwd-file { driver = passwd-file auth_username_format = %{user | username} passwd_file_path = /etc/dovecot/alternate/passwd skip = authenticated } I haven't changed the /etc/dovecot/alternate/passwd in ages and its contents look similar to: user:$6$blablablagfsgfsgfsgsbfssfslongbase64stringhere Just earlier today (on 2.3) I was able to login just fine with the alternate password for my user. Did I misconfigure dovecot or are $6$ type passwords no longer supported. Here's the debug output: 2025-11-10 05:44:58 +0100auth(userhere,server-ip-here,sasl:plain)<VrJZMTZD7rtcKosF>: Debug: pam: Finished passdb lookup 2025-11-10 05:44:58 +0100auth(userhere,server-ip-here,sasl:plain)<VrJZMTZD7rtcKosF>: Debug: passwd-file: Performing passdb lookup 2025-11-10 05:44:58 +0100auth(userhere,server-ip-here,sasl:plain)<VrJZMTZD7rtcKosF>: Debug: passwd-file: lookup: user=userhere file=/etc/dovecot/alternate/passwd 2025-11-10 05:44:58 +0100auth(userhere,server-ip-here,sasl:plain)<VrJZMTZD7rtcKosF>: Debug: passwd-file: Finished passdb lookup 2025-11-10 05:44:58 +0100auth(userhere,server-ip-here,sasl:plain)<VrJZMTZD7rtcKosF>: Debug: Auth request finished 2025-11-10 05:44:58 +0100auth(userhere,server-ip-here,sasl:plain)<VrJZMTZD7rtcKosF>: Debug: delaying auth failure Any idea what might be going on? Cheers, K. C.

2 4

Panic: file mail-user.c: line 185 (mail_user_deinit): assertion failed: ((*user)->refcount == 1)
by Szőts Ákos 10 Nov '25

10 Nov '25

Hi everyone, When I'm running a force-resync on my mailbox, it crashes. Unfortunately, after the crash, it left multiple new FTS mailboxes. Command: doveadm -D force-resync -u user(a)domain.ext '*' Error message: doveadm: Debug: Mailbox INBOX/fts-flatcurve/current.1756202040958990: Mailbox opened doveadm: Error: Mailbox INBOX: FTS optimize failed doveadm: Error: cmd force-resync: Forcing a resync on mailbox INBOX failed: FTS optimize failed doveadm: Panic: file mail-user.c: line 185 (mail_user_deinit): assertion failed: ((*user)->refcount == 1) doveadm: Error: Raw backtrace: #0 fatal_handler_real[0x7f7fcd996190] -> #1 default_fatal_handler[0x7f7fcd996260] -> #2 i_panic[0x7f7fcd8b5407] -> #3 mail_user_deinit.cold[0x7f7fcdc5720e] -> #4 doveadm_mail_next_user[0x55b93b0c16b0] -> #5 doveadm_cmd_ver2_to_mail_cmd_wrapper[0x55b93b0c33d0] -> #6 doveadm_cmdline_run[0x55b93b0d76e0] -> #7 doveadm_cmdline_try_run[0x55b93b0d7ee0] -> #8 main[0x55b93b0b0d10] -> #9 __libc_start_call_main[0x7f7fcd50827e] -> #10 __libc_start_main_alias_2[0x7f7fcd50833e] -> #11 _start[0x55b93b0b1320] Backtrace: #0 __pthread_kill_implementation(threadid=<optimized out>, signo=signo@entry=6, no_tid=no_tid@entry=0) at pthread_kill.c:44 #1 0x00007f7fcd57ae33in __pthread_kill_internal(threadid=<optimized out>, signo=6) at pthread_kill.c:89 #2 0x00007f7fcd51f7b6in __GI_raise(sig=sig@entry=6) at ../sysdeps/posix/raise.c:26 #3 0x00007f7fcd50634bin __GI_abort() at abort.c:77 #4 0x00007f7fcd8b5575in default_fatal_finish(type=LOG_TYPE_PANIC, status=0) at ../lib/failures.c:461 #5 fatal_handler_real(ctx=<optimized out>, format=<optimized out>, args=<optimized out>) at ../lib/failures.c:473 #6 0x00007f7fcd996283in default_fatal_handler(ctx=<optimized out>, format=<optimized out>, args=<optimized out>) at ../lib/failures.c:481 #7 0x00007f7fcd8b54d7in i_panic(format=format@entry=0x7f7fcdd3eac8 "file %s: line %d (%s): assertion failed: (%s)") at ../lib/failures.c:526 #8 0x00007f7fcdc57237in mail_user_deinit(user=<optimized out>) at /usr/src/debug/dovecot-2.4.2/src/lib-storage/mail-user.c:185 #9 mail_user_deinit(user=<optimized out>) at /usr/src/debug/dovecot-2.4.2/src/lib-storage/mail-user.c:183 #10 0x000055b93b0c18f2in doveadm_mail_next_user(ctx=0x55b93ed9dfb8, error_r=<optimized out>) at /usr/src/debug/dovecot-2.4.2/src/doveadm/doveadm-mail.c:505 #11 0x000055b93b0c35e7in doveadm_mail_cmd_exec(ctx=0x55b93ed9dfb8, wildcard_user=0x0) at /usr/src/debug/dovecot-2.4.2/src/doveadm/doveadm-mail.c:705 #12 doveadm_cmd_ver2_to_mail_cmd_wrapper(cctx=<optimized out>) at /usr/src/debug/dovecot-2.4.2/src/doveadm/doveadm-mail.c:1034 #13 0x000055b93b0d7dd7in doveadm_cmdline_run(argc=<optimized out>, argv=0x55b93ed69840, cctx=cctx@entry=0x55b93ed90fa8) at /usr/src/debug/dovecot-2.4.2/src/doveadm/doveadm-cmd-parse.c:451 #14 0x000055b93b0d7f8cin doveadm_cmdline_try_run(cmd_name=cmd_name@entry=0x55b93ed6987c "force-resync", argc=<optimized out>, argv=<optimized out>, cctx=cctx@entry=0x55b93ed90fa8) at /usr/src/debug/dovecot-2.4.2/src/doveadm/doveadm-cmd.c:160 #15 0x000055b93b0b101din main(argc=<optimized out>, argv=<optimized out>) at /usr/src/debug/dovecot-2.4.2/src/doveadm/doveadm.c:406 Unfortunately, this interrupted run left many new mailboxes in place: $ doveadm mailbox list -u user(a)domain.ext Junk Drafts Drafts/fts-flatcurve Drafts/fts-flatcurve/current.1756201209435330 Drafts/fts-flatcurve/index.5092 Trash Trash/fts-flatcurve Trash/fts-flatcurve/current.1756242793225435 Trash/fts-flatcurve/index.5401 Trash/Junk Trash/Junk/fts-flatcurve Trash/Junk/fts-flatcurve/index.6279 Trash/Junk/fts-flatcurve/current.1756366793619309 Interestingly, a short ago I deleted the Junk mailbox with "doveadm mailbox delete -e Junk". Trash/Junk was never a thing. Version: 2.4.2 In case FTS config is useful: mail_plugins { fts = yes fts_flatcurve = yes quota = yes virtual = yes } fts flatcurve { substring_search = yes } fts_autoindex = yes language en { default = yes } language de { } language_tokenizers = generic email-address Ákos Hi everyone, When I'm running a force-resync on my mailbox, it crashes. Unfortunately, after the crash, it left multiple new FTS mailboxes. Command: doveadm -D force-resync -u [1]user(a)domain.ext '*' Error message: doveadm: Debug: Mailbox INBOX/fts-flatcurve/current.1756202040958990: Mailbox opened doveadm: Error: Mailbox INBOX: FTS optimize failed doveadm: Error: cmd force-resync: Forcing a resync on mailbox INBOX failed: FTS optimize failed doveadm: Panic: file mail-user.c: line 185 (mail_user_deinit): assertion failed: ((*user)->refcount == 1) doveadm: Error: Raw backtrace: #0 fatal_handler_real[0x7f7fcd996190] -> #1 default_fatal_handler[0x7f7fcd996260] -> #2 i_panic[0x7f7fcd8b5407] -> #3 mail_user_deinit.cold[0x7f7fcdc5720e] -> #4 doveadm_mail_next_user[0x55b93b0c16b0] -> #5 doveadm_cmd_ver2_to_mail_cmd_wrapper[0x55b93b0c33d0] -> #6 doveadm_cmdline_run[0x55b93b0d76e0] -> #7 doveadm_cmdline_try_run[0x55b93b0d7ee0] -> #8 main[0x55b93b0b0d10] -> #9 __libc_start_call_main[0x7f7fcd50827e] -> #10 __libc_start_main_alias_2[0x7f7fcd50833e] -> #11 _start[0x55b93b0b1320] Backtrace: #0 __pthread_kill_implementation (threadid=<optimized out>, signo=signo@entry=6, no_tid=no_tid@entry=0) at pthread_kill.c:44 #1 0x00007f7fcd57ae33 in __pthread_kill_internal (threadid=<optimized out>, signo=6) at pthread_kill.c:89 #2 0x00007f7fcd51f7b6 in __GI_raise (sig=sig@entry=6) at ../sysdeps/posix/raise.c:26 #3 0x00007f7fcd50634b in __GI_abort () at abort.c:77 #4 0x00007f7fcd8b5575 in default_fatal_finish (type=LOG_TYPE_PANIC, status=0) at ../lib/failures.c:461 #5 fatal_handler_real (ctx=<optimized out>, format=<optimized out>, args=<optimized out>) at ../lib/failures.c:473 #6 0x00007f7fcd996283 in default_fatal_handler (ctx=<optimized out>, format=<optimized out>, args=<optimized out>) at ../lib/failures.c:481 #7 0x00007f7fcd8b54d7 in i_panic (format=format@entry=0x7f7fcdd3eac8 "file %s: line %d (%s): assertion failed: (%s)") at ../lib/failures.c:526 #8 0x00007f7fcdc57237 in mail_user_deinit (user=<optimized out>) at /usr/src/debug/dovecot-2.4.2/src/lib-storage/mail-user.c:185 #9 mail_user_deinit (user=<optimized out>) at /usr/src/debug/dovecot-2.4.2/src/lib-storage/mail-user.c:183 #10 0x000055b93b0c18f2 in doveadm_mail_next_user (ctx=0x55b93ed9dfb8, error_r=<optimized out>) at /usr/src/debug/dovecot-2.4.2/src/doveadm/doveadm-mail.c:505 #11 0x000055b93b0c35e7 in doveadm_mail_cmd_exec (ctx=0x55b93ed9dfb8, wildcard_user=0x0) at /usr/src/debug/dovecot-2.4.2/src/doveadm/doveadm-mail.c:705 #12 doveadm_cmd_ver2_to_mail_cmd_wrapper (cctx=<optimized out>) at /usr/src/debug/dovecot-2.4.2/src/doveadm/doveadm-mail.c:1034 #13 0x000055b93b0d7dd7 in doveadm_cmdline_run (argc=<optimized out>, argv=0x55b93ed69840, cctx=cctx@entry=0x55b93ed90fa8) at /usr/src/debug/dovecot-2.4.2/src/doveadm/doveadm-cmd-parse.c:451 #14 0x000055b93b0d7f8c in doveadm_cmdline_try_run (cmd_name=cmd_name@entry=0x55b93ed6987c "force-resync", argc=<optimized out>, argv=<optimized out>, cctx=cctx@entry=0x55b93ed90fa8) at /usr/src/debug/dovecot-2.4.2/src/doveadm/doveadm-cmd.c:160 #15 0x000055b93b0b101d in main (argc=<optimized out>, argv=<optimized out>) at /usr/src/debug/dovecot-2.4.2/src/doveadm/doveadm.c:406 Unfortunately, this interrupted run left many new mailboxes in place: $ doveadm mailbox list -u [2]user(a)domain.ext Junk Drafts Drafts/fts-flatcurve Drafts/fts-flatcurve/current.1756201209435330 Drafts/fts-flatcurve/index.5092 Trash Trash/fts-flatcurve Trash/fts-flatcurve/current.1756242793225435 Trash/fts-flatcurve/index.5401 Trash/Junk Trash/Junk/fts-flatcurve Trash/Junk/fts-flatcurve/index.6279 Trash/Junk/fts-flatcurve/current.1756366793619309 Interestingly, a short ago I deleted the Junk mailbox with "doveadm mailbox delete -e Junk". Trash/Junk was never a thing. Version: 2.4.2 In case FTS config is useful: mail_plugins { fts = yes fts_flatcurve = yes quota = yes virtual = yes } fts flatcurve { substring_search = yes } fts_autoindex = yes language en { default = yes } language de { } language_tokenizers = generic email-address Akos References Visible links 1. mailto:user@domain.ext 2. mailto:user@domain.ext

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doveadm sync: Both source and destination mail_path and mail_index_path point to same directory
by Szőts Ákos 09 Nov '25

09 Nov '25

Hi everyone, When I'm trying to synchronise my e-mails from a backup with doveadm sync, I get an error. Doveadmin sync command: doveadm -D sync -1 -f -a "Virtual/All" -R -u user(a)example.net -n inbox mdbox:/var/spool/mail/example.net/user_backup Error message: dsync: Error: cmd sync: Both source and destination mail_path and mail_index_path point to same directory: /var/spool/mail/example.net/user//mail/mailboxes (name space inbox { mail_path } is set explicitly?) Relevant config section: namespace inbox { separator = / inbox = yes # "home" is set in userdb mail_path = %{home}/mail mail_index_path = %{home}/index/inbox mailbox ... { ... } mailbox ... { ... } } mail_driver = mdbox According to the config, the two directories are explicitly set to be different. I verified and they exist and they are not symlinks. Do you know what causes this issue? Version: 2.4.2 Thank you, Ákos Hi everyone, When I'm trying to synchronise my e-mails from a backup with doveadm sync, I get an error. Doveadmin sync command: doveadm -D sync -1 -f -a "Virtual/All" -R -u [1]user(a)example.net -n inbox mdbox:/var/spool/mail/example.net/user_backup Error message: dsync: Error: cmd sync: Both source and destination mail_path and mail_index_path point to same directory: /var/spool/mail/example.net/user//mail/mailboxes (name space inbox { mail_path } is set explicitly?) Relevant config section: namespace inbox { separator = / inbox = yes # "home" is set in userdb mail_path = %{home}/mail mail_index_path = %{home}/index/inbox mailbox ... { ... } mailbox ... { ... } } mail_driver = mdbox According to the config, the two directories are explicitly set to be different. I verified and they exist and they are not symlinks. Do you know what causes this issue? Version: 2.4.2 Thank you, Akos References Visible links 1. mailto:user@example.net

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Using full email address as login
by Alex 07 Nov '25

07 Nov '25

Hi, I'm using dovecot-2.3.21.1 on fedora42. It seems that increasingly remote clients are only supporting the full email address as the login ID instead of just the username. One such example is Apollo.io, an AI sales platform that uses IMAP to connect to a remote server to send and receive emails. The documentation I've found on this appears to be deprecated or incomplete. Do I want to look for "shared namespace" documentation? Currently, emails are stored in /var/spool/mail/username. Does this need to change to something like /var/spool/domain.com/username? I'll also need to change postfix to use username(a)domain.com with sasl, I believe? Here is my current dovecot.conf. Ideas greatly appreciated. # 2.3.21.1 (d492236fa0): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5.21.1 (49005e73) # OS: Linux 6.17.6-200.fc42.x86_64 x86_64 Fedora release 42 (Adams) # Hostname: orion.example.com auth_mechanisms = plain xoauth2 oauthbearer auth_verbose = yes default_vsz_limit = 1500 M mail_gid = mail mail_home = mail/ mail_location = mbox:~/mail:INBOX=/var/spool/mail/%u mail_max_userip_connections = 500 mail_plugins = " listescape acl" mail_privileged_group = mail managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext mbox_write_locks = fcntl namespace inbox { inbox = yes location = mailbox Drafts { special_use = \Drafts } mailbox Junk { special_use = \Junk } mailbox Sent { special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { special_use = \Trash } prefix = } passdb { driver = pam } protocols = imap pop3 service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0660 user = postfix } } service imap-login { inet_listener imaps { address = 68.195.111.42 port = 993 } process_min_avail = 6 service_count = 0 } service pop3-login { inet_listener pop3 { address = 127.0.0.1 port = 110 } inet_listener pop3s { port = 995 } } ssl_cert = </etc/letsencrypt/example-fullchain.pem ssl_cipher_list = ALL:!LOW:!EXP:!aNULL:!RC4::!eNULL:!LOW:!3DES:!MD5:!EXP:!PSK:!SRP:!DSS ssl_key = # hidden, use -P to show it ssl_prefer_server_ciphers = yes userdb { driver = passwd } Thanks, Alex Hi, I'm using dovecot-2.3.21.1 on fedora42. It seems that increasingly remote clients are only supporting the full email address as the login ID instead of just the username. One such example is Apollo.io, an AI sales platform that uses IMAP to connect to a remote server to send and receive emails. The documentation I've found on this appears to be deprecated or incomplete. Do I want to look for "shared namespace" documentation? Currently, emails are stored in /var/spool/mail/username. Does this need to change to something like /var/spool/[1]domain.com/username? I'll also need to change postfix to use [2]username(a)domain.com with sasl, I believe? Here is my current dovecot.conf. Ideas greatly appreciated. # 2.3.21.1 (d492236fa0): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5.21.1 (49005e73) # OS: Linux 6.17.6-200.fc42.x86_64 x86_64 Fedora release 42 (Adams) # Hostname: [3]orion.example.com auth_mechanisms = plain xoauth2 oauthbearer auth_verbose = yes default_vsz_limit = 1500 M mail_gid = mail mail_home = mail/ mail_location = mbox:~/mail:INBOX=/var/spool/mail/%u mail_max_userip_connections = 500 mail_plugins = " listescape acl" mail_privileged_group = mail managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext mbox_write_locks = fcntl namespace inbox { inbox = yes location = mailbox Drafts { special_use = \Drafts } mailbox Junk { special_use = \Junk } mailbox Sent { special_use = \Sent } mailbox "Sent Messages" { special_use = \Sent } mailbox Trash { special_use = \Trash } prefix = } passdb { driver = pam } protocols = imap pop3 service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0660 user = postfix } } service imap-login { inet_listener imaps { address = 68.195.111.42 port = 993 } process_min_avail = 6 service_count = 0 } service pop3-login { inet_listener pop3 { address = 127.0.0.1 port = 110 } inet_listener pop3s { port = 995 } } ssl_cert = </etc/letsencrypt/example-fullchain.pem ssl_cipher_list = ALL:!LOW:!EXP:!aNULL:!RC4::!eNULL:!LOW:!3DES:!MD5:!EXP:!PSK:!SRP:!DSS ssl_key = # hidden, use -P to show it ssl_prefer_server_ciphers = yes userdb { driver = passwd } Thanks, Alex References Visible links 1. http://domain.com/username 2. mailto:username@domain.com 3. http://orion.example.com/

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2.4.2 upgrade oddity
by Andy Baugh 06 Nov '25

06 Nov '25

Howdy y'all, I noticed something odd with the userdb/passdb processing past the 2.4.2 CVE fix, etc. -- namely that the prefixing you previously needed to do to userdb returns, etc. when you set a cache_key is no longer necessary and in fact harmful. It is worth mentioning, as after looking into this a bit and realizing that it "should have been obvious" to me that this would have been the case. That said I didn't make the logical leap till doveadm screamed at me about it during mailbox creation after upgrade (can't very well do `doveadm mailbox create -s -u user(a)domain.test INBOX.spam` when your userdb returns `${CACHE_KEY}_mailbox/INBOX/spam/...` for the relevant config values, etc.). TL;DR: disabling the cache = do NOT prefix any userdb/passdb returns in accordance with cache_key you set. This is true for lua passdb/authdb or any other authdb, not just passwd/oauth2. Cheers, -- Thomas "Andy" Baugh | Software Development Engineer IV andy.baugh(a)webpros.com www.webpros.com

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doveadm sync issue
by Dan Whitehouse 06 Nov '25

06 Nov '25

Hi, I am running Dovecot on Debian trixie (dovecot-core/stable,now 1:2.4.1+dfsg1-6 amd64). Under the previous version, which I believe was 2.3, I was able to run a sync script with the following syntax: doveadm sync -u <user> remote:<user>@<host.tld> This worked very well and I was able to sync my mail. Having upgraded, this syntax produces the following error: dsync-server: invalid option -- ‘U' Error: doveadm: Unexpected or incomplete option: -U Even though my script doesn’t pass “-U” explicitly I believe that it is passed internally: https://github.com/dovecot/core/blob/main/src/doveadm/doveadm-settings.c#L1… core/src/doveadm/doveadm-settings.c at main · dovecot/core github.com Confusingly the online help still displays: doveadm dsync-server —help doveadm dsync-server [-r <rawlog path>] [-T <timeout secs>] [-U] Here we can see that the “-U” option (despite all the above) appears to have been removed from the code: https://github.com/dovecot/core/commit/4c04e4c30fd4817a8b0e11d04d9681173f69… global: Remove replicator · dovecot/core@4c04e4c github.com I have added the following to /etc/dovecot/local.conf: dsync_remote_cmd = "ssh -l%{login} %{host} doveadm dsync-server -u%{user}” (Note that I override the “-U”) and sync once again works properly. Many thanks for your attention, Dan Whitehouse

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