Ok running :

freebsd-12.1
dovecot-2.3.18.current
dovecot-2.3-pigeonhole-0.5.18.current

simply put replication works fine on smaller email boxes without issues.

dsync also works when run manually, longest sync is 60 secords or so when using dsync so need replicator bumped up ?

i get the fact that the file locking issue relative since a larger mailbox will take longer to replicate when an email comes in ?

mail18      03-05 18:05:51 {dovecot}        [15799] (872623573) doveadm(keith@elirpa.com)<32249><GnS3M53sI2L5fQAAz1jc/w>: Error: Couldn't lock
                                                    /data/dovecot/users/elirpa.com/keith@elirpa.com//tmp/.dovecot-sync.lock:
                                                    fcntl(/data/dovecot/users/elirpa.com/keith@elirpa.com//tmp/.dovecot-sync.lock, write-lock, F_SETLKW)
                                                    locking failed: Timed out after 30 seconds (WRITE lock held by pid 31519)

so what i need is where fcntl is setting a 30 second timeout for replication (i have adjust all the others in the src code)

simply put replicator fails and retries and keeps failing which is understandable as it probably needs a little more time ?

# sync.users
carol@scom.ca                     none     00:02:51  08:16:34  -            y   
nick@elirpa.com                   low      02:45:17  09:28:32  -            y   
keith@elirpa.com                  none     02:30:13  09:28:32  -            y   
paul@scom.ca                      high     02:45:17  09:28:32  -            y   
ed@scom.ca                        none     02:34:34  09:28:32  -            y   
ed.hanna@dssmgmt.com              high     02:45:17  09:28:32  -            y  

i found under /programs/src/mail/dovecot-2.3.18.current/src/lib

file-lock.c

    struct flock fl;

    fl.l_type = lock_type;
    fl.l_whence = SEEK_SET;
    fl.l_start = 0;
    fl.l_len = 0;

    ret = fcntl(fd, timeout_secs != 0 ? F_SETLKW : F_SETLK, &fl);
    if (timeout_secs != 0) {
      alarm(0);
      file_lock_wait_end(path);
    }

    if (ret == 0)
      break;

    if (timeout_secs == 0 &&
        (errno == EACCES || errno == EAGAIN)) {
      /* locked by another process */
      *error_r = t_strdup_printf(
        "fcntl(%s, %s, F_SETLK) locking failed: %m "
        "(File is already locked)", path, lock_type_str);
      return 0;
    }

    if (err_is_lock_timeout(started, timeout_secs)) {
      errno = EAGAIN;
      *error_r = t_strdup_printf(
        "fcntl(%s, %s, F_SETLKW) locking failed: "
        "Timed out after %u seconds%s",
        path, lock_type_str, timeout_secs,
        file_lock_find(fd, set->lock_method,
                 lock_type));
      return 0;
    }
    *error_r = t_strdup_printf("fcntl(%s, %s, %s) locking failed: %m",
      path, lock_type_str, timeout_secs == 0 ? "F_SETLK" : "F_SETLKW");
    if (errno == EDEADLK && !set->allow_deadlock) {
      i_panic("%s%s", *error_r,
        file_lock_find(fd, set->lock_method,
                 lock_type));
    }
    return -1;
#endif
--


Happy Saturday !!!
Thanks - paul

Paul Kudla


Scom.ca Internet Services
004-1009 Byron Street South
Whitby, Ontario - Canada
L1N 4S3

Toronto 416.642.7266
Main 1.866.411.7266
Fax 1.888.892.7266