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@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@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)