Can anyone tell me what the below messages mean? I didn’t find many hits on the web:

Sep 14 13:15:45 atlrdtd1 avahi-daemon[6709]: Interface bond0.IPv6 no longer relevant for mDNS.
Sep 14 13:15:45 atlrdtd1 avahi-daemon[6709]: Leaving mDNS multicast group on interface bond0.IPv6 with address fe80::204:23ff:feba:f120.
Sep 14 13:15:45 atlrdtd1 avahi-daemon[6709]: Interface bond0.IPv4 no longer relevant for mDNS.
Sep 14 13:15:45 atlrdtd1 avahi-daemon[6709]: Leaving mDNS multicast group on interface bond0.IPv4 with address 192.168.8.73.
Sep 14 13:15:45 atlrdtd1 avahi-daemon[6709]: Withdrawing address record for fe80::204:23ff:feba:f120 on bond0.
Sep 14 13:15:45 atlrdtd1 avahi-daemon[6709]: Withdrawing address record for 192.168.8.73 on bond0.
Sep 14 13:15:45 atlrdtd1 avahi-daemon[6709]: New relevant interface bond0.IPv4 for mDNS.
Sep 14 13:15:45 atlrdtd1 avahi-daemon[6709]: Joining mDNS multicast group on interface bond0.IPv4 with address 192.168.8.73.
Sep 14 13:15:45 atlrdtd1 avahi-daemon[6709]: Registering new address record for 192.168.8.73 on bond0.
Sep 14 13:15:45 atlrdtd1 avahi-daemon[6709]: Interface eth2.IPv6 no longer relevant for mDNS.
Sep 14 13:15:45 atlrdtd1 avahi-daemon[6709]: Leaving mDNS multicast group on interface eth2.IPv6 with address fe80::204:23ff:feba:f120.
Sep 14 13:15:45 atlrdtd1 avahi-daemon[6709]: Withdrawing address record for fe80::204:23ff:feba:f120 on eth2.
Sep 14 13:15:45 atlrdtd1 kernel: bonding: bond0: Interface eth2 is already enslaved!
Sep 14 13:15:45 atlrdtd1 avahi-daemon[6709]: Interface eth3.IPv6 no longer relevant for mDNS.
Sep 14 13:15:45 atlrdtd1 avahi-daemon[6709]: Leaving mDNS multicast group on interface eth3.IPv6 with address fe80::204:23ff:feba:f120.
Sep 14 13:15:45 atlrdtd1 avahi-daemon[6709]: Withdrawing address record for fe80::204:23ff:feba:f120 on eth3.
Sep 14 13:15:45 atlrdtd1 kernel: bonding: bond0: Interface eth3 is already enslaved!
Sep 14 13:15:47 atlrdtd1 avahi-daemon[6709]: New relevant interface bond0.IPv6 for mDNS.
Sep 14 13:15:47 atlrdtd1 avahi-daemon[6709]: Joining mDNS multicast group on interface bond0.IPv6 with address fe80::204:23ff:feba:f120.
Sep 14 13:15:47 atlrdtd1 avahi-daemon[6709]: Registering new address record for fe80::204:23ff:feba:f120 on bond0.

Background:
We have an Oracle RAC cluster of 2 nodes. One of the nodes rebooted and its log indicates that Oracle forced the reboot to preserve cluster integrity. There were no other messages in that node’s /var/log/messages near the time of this message and reboot.

We use a private LAN setup on 2 bonded NICs on each side for the Oracle Cluster Ready Services to communicate with each other. That is bond0 and is using 2 Intel GigE NIC ports on both sides (eth2 and eth3 are the NICs). We found that the connectivity on the private LAN had gone away and on checking found that both eth2 and eth3 on the node that got these messages was showing no link. Running “ifdown bond0” followed by “ifup bond0” re-established links on both eth2 and eth3.

The above messages occurred on the node where bond0’s links were down less than 2 minutes before the node that rebooted issued the message about shutting down to preserve cluster integrity. It seems fairly clear the cause of the reboot was the loss of connectivity but I can’t really determine from the above log entries WHY bond0 went down. So was hoping someone had seen something like this and could give me a clue.

Both nodes are RHEL5 servers.

P.S. We don’t actually use the ipv6 – the relevant addresses are the ipv4 ones. Apparently the guy who set this up didn’t disable ipv6 on these NICs but I don’t believe that is the issue as they have been up for a few months with this configuration.

As my understand, it simply is the informations during communication with DHCP server.

Given that the messages say nothing about DHCP I'm curious what makes you think this has something to do with DHCP?

For the record we aren't using DHCP for this bond0 - it has a static address defined in ifcfg-bond0. bootproto for it and the two NICs (ifcfg-eth2 and ifcfg-eth3) is set to "none" so there should be no reason for anything to be attempting DHCP for the bonding.