The output in the exhibit indicates that the node's network interfaces (eth0-eth3) are bonded together using LACP (Link Aggregation Control Protocol) with 'balance-tcp' as the bonding mode and LACP speed set to
'fast'. For LACP to function correctly, the switch ports to which the node is connected must also be configured to support LACP. If the ports on the upstream switch are not configured for LACP, the bond will not be able to establish properly, and the node will not communicate effectively on the network, making it undiscoverable when attempting to expand the cluster.
The absence of an operational LACP configuration could prevent the new node from joining the existing cluster as the node's network interfaces would not be able to pass traffic correctly. This can be verified by checking the switch configuration to ensure that the ports are set to participate in an LACP bond.
The other options, such as a firewall blocking discovery traffic (Option A) or the node being on different VLANs (Option C), are possible causes for a node not being discovered, but given the specific command output provided, the most likely cause is related to the switch port configuration for LACP. Option D, regarding completing LACP configuration after cluster expansion, is not correct because LACP needs to be operational for the node to communicate with the cluster during the expansion process.
Proper LACP configuration is critical for network communication in a Nutanix AHV cluster, and this is covered in detail in the Nutanix AHV and Networking documentation. It outlines the steps for configuring network bonds and LACP on both the AHV hosts and the connecting network infrastructure.