Mastering Proxmox - Third Edition

Multicast

From Proxmox VE 4.0 and later, multicast is now required for proper cluster communication. In simple words, multicast delivers a single transmission to multiple server nodes in a network simultaneously, whereas unicast sends data packets to a single destination from a single source. The more nodes there are in a cluster, the more separate unicast packets need to be sent by it. Using multicast, this extra amount of traffic is vastly minimized. Due to the increase of packets in the network when using unicast, implementing it in a cluster with five or more nodes should be avoided. In order for multicast to work, the physical switch in the network must be multicast and IGMP snoop capable.

IGMP snooping is simply a process where the ...