Mail server backup using dsync

Hi,

I would like to backup our mail server running Mountain Lion and Server 2.2.2. I know that mail server basically is Dovecot wich has dsync utility with backup function. I tried to use it but no success. When I enter dsync -u bek backup maildir:/tmp/mail_backup2/ it makes new directory but the size is 0b. When I try to enable verbose and debug mode I get this:

sh-3.2# dsync -v -D -u bek backup maildir:/tmp/Mail_backup2

dsync(root): Debug: Added userdb setting: plugin/quota=maildir:User quota:noenforcing

dsync(root): Debug: Added userdb setting: plugin/quota_rule=*:storage=0

dsync(root): Debug: Added userdb setting: mail=maildir:/Library/Server/Mail/Data/mail/67AD2845-053A-467C-B0C1-D897CF93CA0 1

dsync(root): Debug: Added userdb setting: mail_location=maildir:/Library/Server/Mail/Data/mail/67AD2845-053A-467C-B0C1-D8 97CF93CA01

dsync(root): Debug: Added userdb setting: plugin/sieve=/Library/Server/Mail/Data/rules/67AD2845-053A-467C-B0C1-D897CF93CA 01/dovecot.sieve

dsync(root): Debug: Added userdb setting: plugin/sieve_dir=/Library/Server/Mail/Data/rules/67AD2845-053A-467C-B0C1-D897CF 93CA01

dsync(root): Debug: Added userdb setting: plugin/sieve_storage=/Library/Server/Mail/Data/rules/67AD2845-053A-467C-B0C1-D8 97CF93CA01

dsync(root): Debug: Effective uid=214, gid=6, home=

dsync(root): Debug: Quota root: name=User quota backend=maildir args=noenforcing

dsync(root): Debug: Quota rule: root=User quota mailbox=* bytes=0 messages=0

dsync(root): Debug: Quota warning: bytes=0 (100%) messages=0 reverse=no command=quota-exceeded bek

dsync(root): Debug: maildir++: root=/Library/Server/Mail/Data/mail/67AD2845-053A-467C-B0C1-D897CF93CA01, index=, control=, inbox=/Library/Server/Mail/Data/mail/67AD2845-053A-467C-B0C1-D897CF93CA01, alt=

dsync(root): Debug: Effective uid=214, gid=6, home=

dsync(root): Debug: Quota root: name=User quota backend=maildir args=noenforcing

dsync(root): Debug: Quota rule: root=User quota mailbox=* bytes=0 messages=0

dsync(root): Debug: Quota warning: bytes=0 (100%) messages=0 reverse=no command=quota-exceeded bek

dsync(root): Debug: maildir++: root=/tmp/Mail_backup2, index=, control=, inbox=/tmp/Mail_backup2, alt=

dsync(root): Debug: Namespace : /tmp/Mail_backup2 doesn't exist yet, using default permissions

dsync(root): Debug: Namespace : Using permissions from /tmp/Mail_backup2: mode=0700 gid=-1

dsync(bek): Debug: Namespace : Using permissions from /Library/Server/Mail/Data/mail/67AD2845-053A-467C-B0C1-D897CF93CA01: mode=0700 gid=-1

dsync(bek): Debug: Namespace : /tmp/Mail_backup2/.Sent Messages doesn't exist yet, using default permissions

dsync(bek): Debug: Namespace : Using permissions from /tmp/Mail_backup2: mode=0700 gid=-1

...

dsync(bek): Info: Sent Messages: only in source (guid=18064939219d4d53075900002c7a8c6a)

dsync(bek): Info: Deleted Messages: only in source (guid=184db229daff33538f3401002c7a8c6a)

dsync(bek): Info: Notes: only in source (guid=b045a70340b82453390200009005ae25)

dsync(bek): Info: Drafts: only in source (guid=b0f540327e9f4f53fafb00002c7a8c6a)

dsync(bek): Info: INBOX: only in source (guid=b145a70340b82453390200009005ae25)

dsync(bek): Info: Sent: only in source (guid=c818f808caff4b53e7cf00002c7a8c6a)

I also would like to sync mail between two servers (primary and backup). Anyone any experience with dsync on OS X? Thanks