How Load sharing Multicast Modes Work

[Nick_Shah]

I was reading Load sharing Multicast Mode on the Checkpoint Forum.  But i did not understand on which basis any one of active cluster member processes ARP request(Point 4), in this case both are active, so how this decision is made ?

Could someone please help me understand this.

This scenario describes a user logging from the Internet to a Web server behind the cluster that is configured in Load Sharing Multicast mode.

1. The user requests a connection from 192.168.10.78 (his computer) to 10.10.0.34 (the Web server).
2. A router on the 192.168.10.x network recognizes 192.168.10.100 (the cluster Virtual IP address) as the default gateway to the 10.10.0.x network.
3. The router issues an ARP Request for IP 192.168.10.100.
4. One of the Active Cluster Members processes the ARP Request, and responds with the Multicast MAC assigned to the cluster Virtual IP address of 192.168.10.100.
5. When the Web server responds to the user requests, it recognizes 10.10.0.100 as its default gateway to the Internet.
6. The Web server issues an ARP Request for IP 10.10.0.100.
7. One of the Active members processes the ARP Request, and responds with the Multicast MAC address assigned to the cluster Virtual IP address of 10.10.0.100.
8. All packets sent between the user and the Web server reach every Cluster Member, which decide whether to process each packet.
9. When a cluster failover occurs, one of the Cluster Members goes down. However, traffic still reaches all of the Active Cluster Members. Therefore, there is no need to make changes in the network ARP routing. The only thing that changes, is the cluster decision function, which takes into account the new state of the Cluster Members.

Thanks,

Nitesh

[_Val_ · Accepted solution]

the decision is made randomly and then saved in hash info. the idea is to spread different connections between cluster members for processing

[_Val_]

More details can be found in the ClusterXL Admin Guide, depending on your version. Look for Load Sharing Mode chapter

For example, here: https://sc1.checkpoint.com/documents/R80.20_GA/WebAdminGuides/EN/CP_R80.20_ClusterXL_AdminGuide/html...