Panic: file dsync-brain-mailbox-tree.c: line 448: unreached

[Marc Weustink]

Hi all,

To backup our imap folders I've a cronjob running in the night:
  /usr/bin/doveadm -o stats_writer_socket_path=  backup -R -A -N 
tcp:xxx.yyy.zzz:4191

This ran successful when I set it up and didn't look at it anymore.
Recently I noticed errors:

dsync-local(administration)<uO/qHjXS6FteLAAA3i05xw>: Panic: file 
dsync-mailbox-tree-sync.c: line 1253 (sync_create_mailboxes): assertion 
failed: (node->ns == other_node->ns)
dsync-local(administration)<uO/qHjXS6FteLAAA3i05xw>: Error: Raw 
backtrace: /usr/lib/dovecot/libdovecot.so.0(+0xcceca) [0x7f7029099eca] 
-> /usr/lib/dovecot/libdovecot.so.0(+0xccf21) [0x7f7029099f21] -> 
/usr/lib/dovecot/libdovecot.so.0(i_fatal+0) [0x7f7029006f44] -> 
/usr/bin/doveadm(+0x5206c) [0x558ba9fec06c] -> 
/usr/bin/doveadm(dsync_mailbox_trees_sync_init+0x2a2) [0x558ba9fedba2] 
-> /usr/bin/doveadm(dsync_brain_recv_mailbox_tree_deletes+0x246) 
[0x558ba9fdf6d6] -> /usr/bin/doveadm(dsync_brain_run+0x5b8) 
[0x558ba9fdbec8] -> /usr/bin/doveadm(+0x42260) [0x558ba9fdc260] -> 
/usr/bin/doveadm(+0x585bf) [0x558ba9ff25bf] -> 
/usr/lib/dovecot/libdovecot.so.0(io_loop_call_io+0x69) [0x7f70290b2029] 
-> /usr/lib/dovecot/libdovecot.so.0(io_loop_handler_run_internal+0x109) 
[0x7f70290b3959] -> 
/usr/lib/dovecot/libdovecot.so.0(io_loop_handler_run+0x52) 
[0x7f70290b2132] -> /usr/lib/dovecot/libdovecot.so.0(io_loop_run+0x38) 
[0x7f70290b2348] -> /usr/bin/doveadm(+0x27e39) [0x558ba9fc1e39] -> 
/usr/bin/doveadm(+0x2a3c7) [0x558ba9fc43c7] -> 
/usr/bin/doveadm(+0x2b1f6) [0x558ba9fc51f6] -> 
/usr/bin/doveadm(doveadm_mail_try_run+0x1fa) [0x558ba9fc597a] -> 
/usr/bin/doveadm(main+0x45b) [0x558ba9fb4ceb] -> 
/lib/x86_64-linux-gnu/libc.so.6(__libc_start_main+0xf0) [0x7f702891a830] 
-> /usr/bin/doveadm(_start+0x29) [0x558ba9fb4e69]
Aborted (core dumped)

I've added the dovecot repo to get dovecot automatically updated, so I 
cannot tell with which version it started.

my doveconf -n:

[sudo] password for infraadmin:
# 2.3.3 (dcead646b): /etc/dovecot/dovecot.conf
# Pigeonhole version 0.5.3 (f018bbab)
# OS: Linux 4.4.0-137-generic x86_64 Ubuntu 16.04.5 LTS autofs
# Hostname: xxx.xxx.xxx
dict {
   acl = pgsql:/etc/dovecot/dovecot-dict-sql-local.conf.ext
}
doveadm_password = # hidden, use -P to show it
mail_debug = yes
mail_gid = vmail
mail_home = /home/mail/backup/%n
mail_location = maildir:/home/mail/backup/%n/mail
mail_uid = vmail
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
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 =
   separator = /
   type = private
}
namespace public {
   location = 
maildir:/home/mail/backup/Common/mail:INDEXPVT=/home/mail/backup/%n/mail/common
   prefix = Common/
   separator = /
   subscriptions = no
   type = public
}
passdb {
   args = /etc/dovecot/dovecot-sql.conf.ext
   driver = sql
}
plugin {
   acl = vfile
   acl_shared_dict = proxy::acl
   sieve = file:~/sieve;active=~/.dovecot.sieve
}
protocols = " sieve"
service auth {
   unix_listener auth-userdb {
     mode = 0777
   }
}
service dict {
   unix_listener dict {
     group = vmail
     user = vmail
   }
}
ssl = no
userdb {
   args = /etc/dovecot/dovecot-sql.conf.ext
   driver = sql
}