LDAP Log

[Mido3mad]

I Found Many of this log in my ldap server ( Multi Server Installation )
Zcs 7.1

tail -f /var/log/zimbra.log

Apr 14 12:53:28 ldab last message repeated 6 times
Apr 14 12:55:29 ldab slapd[1977]: slap_queue_csn: queing 0x43efe540 20120414105529.734258Z#000000#000#000000
Apr 14 12:55:29 ldab slapd[1977]: slap_graduate_commit_csn: removing 0x137853b0 20120414105529.734258Z#000000#000#000000
Apr 14 12:55:33 ldab slapd[1977]: connection_read(13): no connection!
Apr 14 12:55:36 ldab last message repeated 6 times
Apr 14 12:57:40 ldab slapd[1977]: connection_read(39): no connection!
Apr 14 12:57:41 ldab last message repeated 7 times
Apr 14 12:59:47 ldab slapd[1977]: connection_read(13): no connection!
Apr 14 12:59:48 ldab last message repeated 5 times
Apr 14 13:01:53 ldab slapd[1977]: connection_read(39): no connection!

what its refer to?

[Mido3mad]

there is no answer?