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.

According to theNutanix Support & Insights, in a two-node ROBO cluster with a witness VM, if one node goes down, the other node sends a leadership request to the witness VM and goes into single-node mode. The cluster remains available and can tolerate another failure of either the witness VM or the network link.

The correct answer is D. Fewer than 30 I/Os and less than 1000 bytes per day of network traffic for the past 21 days.

A zombie VM is a type of inactive VM that is powered on but does very little activity. A zombie VM wastes host resources such as CPU, memory, disk, and network that could be used by other VMs. A zombie VM can be identified by using the VM Profile feature in Prism Central. The VM Profile feature analyzes the resource utilization of each VM and assigns it a profile based on its efficiency and impact on other VMs. The profiles are as follows1:

Efficient: The VM is well-provisioned and has optimal resource utilization.

Over-provisioned: The VM has more resources than it needs and has low resource utilization.

Constrained: The VM has less resources than it needs and has high resource utilization.

Inactive: The VM has no resource utilization and is idle or powered off.

Bully: The VM has high resource utilization and causes contention for other VMs.

A zombie VM is a subtype of an inactive VM that meets the following criteria2:

The VM is powered on for the past 21 days.

The VM does fewer than 30 read or write I/Os (total) per day for the past 21 days.

The VM receives or transfers fewer than 1000 bytes per day of network traffic for the past 21 days.

To identify a zombie VM, the administrator can use Prism Central to view the VM Profile dashboard and filter by profile type. The dashboard shows the number of VMs in each profile type, as well as their resource consumption and efficiency score. The administrator can also drill down into each VM to see its detailed metrics and recommendations for optimization.

This is because Nutanix uses a distributed storage fabric (DSF) that replicates data across multiple nodes and drives to ensure data resiliency. When a drive fails, the cluster detects the failure and initiates a data rebuild process to restore the replication factor (RF) of the affected containers. The data rebuild process does not affect the availability or performance of the VMs, as they can still access their data from other replicas on other nodes or drives. Therefore, there is no need to wait for 60 minutes, use a shared volume group, or trigger an HA event.

A managed network is a type of network that can be created on an AHV cluster and allows VMs to automatically be assigned an IP address at creation time. A managed network uses the Nutanix IP Address Management (IPAM) service, which provides DHCP and DNS functionality for the VMs on the network. A managed network can be configured with a subnet range, a default gateway, and DNS servers. The IPAM service will allocate IP addresses from the subnet range to the VMs and register their hostnames in the DNS servers.The IPAM service will also release the IP addresses when the VMs are deleted or moved to another network1.

To create a managed network on an AHV cluster, the administrator can use Prism Element or Prism Central.The steps are as follows2:

In Prism Element, go to the Network Configuration page and click Create Network.

In Prism Central, go to the Networks page and click Create.

Enter a name and description for the network.

Select Managed as the network type.

Enter the subnet range, default gateway, and DNS servers for the network.

Optionally, enable VLAN tagging and enter a VLAN ID for the network.

Click Save.