An Ethernet failure can be caused by the failure of an Ethernet card, Ethernet port, or Ethernet cable. If a failure occurs, the Lotus Sametime Unified Telephony node's Linux bonding driver switches the IP address to the second Ethernet port on the same Lotus Sametime Unified Telephony node, then sends out a gratuitous ARP to update the routing tables in the LAN switch.
If an Ethernet port fails, that port is switched to its backup port connected to the node's other Ethernet switch. Any traffic on that system component routes to the new Ethernet switch on its path, via the gigabit link to the original Ethernet switch, and continues to its original destination.
For example, if the port to switch A on Node 1 fails, the following takes place:
- All the data switches to the port to switch B on Node 1.
- The data passes from the Ethernet switch B, through the Gbit link, to the Ethernet switch A connected to the failed port.
- The data continues on its intended route.
The Figure below provides an example of this operation. The Ethernet card with the primary port for signaling (eth2) and the second cluster interconnect (eth3) has failed, so the backup port (eth6) has assumed the primary port's (eth2) functionality. Although the second cluster interconnect (eth3) is lost, all interconnect traffic can still flow through the first cluster-interconnect (eth1).
Parent topic: Cluster Redundancy