A bond is a logical interface that combines two or more physical interfaces on an AHV host. A bond provides high availability and load balancing for the network traffic of the host and its VMs. A bond can have different modes that determine how the traffic is distributed and how the bond handles failures of the physical interfaces. The most common bond modes are active-backup, active-active, and LACP1.

Nutanix recommends including at least two physical interfaces in every bond to ensure high availability and redundancy. If one of the physical interfaces fails or is disconnected, the other interface can take over the traffic without affecting the connectivity of the host or its VMs. Having at least two physical interfaces in a bond also allows for maintenance operations such as firmware upgrades or cable replacements without downtime2.

Nutanix does not recommend including NIC models from different vendors in the same bond, as this may cause compatibility issues or performance degradation. Nutanix also does not recommend using only one physical interface in a bond, as this provides no redundancy or load balancing benefits3.

The default network configuration for AHV hosts and CVMs is a bond named br0-up with two or more uplinks in active-backup mode. This means that only one uplink is active at a time, while the others are in standby mode. This provides high availability, but not load balancing or increased bandwidth. To increase the bandwidth available to the AHV host and the CVM, the administrator can change the bond mode to Active-Active, which allows all uplinks to be used simultaneously. This can be done using the manage-ovs commands on each AHV host. The steps are as follows1:

• Log in to the AHV host using SSH.
• Enter maintenance mode on the CVM by running allssh 'cluster status | grep -i cvm | grep -i down'.
• Change the bond mode to Active-Active by running manage_ovs --bond_mode active-active update_uplinks br0-up , where  is a comma-separated list of uplink interfaces (for example, eth0,eth1).
• Verify the bond mode by running manage_ovs show_uplinks.
• Exit maintenance mode on the CVM by running allssh 'cluster start'.

The best way to configure the VM for optimal performance is to set it up with 2 vNUMA nodes. This will ensure that the VM is configured to take advantage of the CPU and memory resources available in each node, and it will also ensure that all of the cores are utilized for the best performance. Additionally, the administrator should ensure that the VM has an affinity policy set up so that the vCPUs are evenly distributed across the four nodes. Finally, Flash Mode should be enabled in order to take advantage of the high-performance SSDs that are available in the cluster

LCM (Life Cycle Manager) is a feature that allows Nutanix administrators to perform one-click firmware and software upgrades for Nutanix clusters and components. LCM fetches inventory and update information from a pre-configured URL that contains the latest versions of firmware and software packages. However, upgrading Nutanix AOS does not automatically update the fetch URL. To update the fetch URL, the administrator needs to update the LCM framework. The LCM framework is the core component of LCM that provides the logic and functionality for inventory, download, and upgrade operations1.

To upgrade the LCM framework, the administrator needs to perform an LCM inventory. An LCM inventory is a process that scans the cluster and its components for their current firmware and software versions and compares them with the available versions from the fetch URL. If there is a newer version of the LCM framework available, it will be shown as an update option under Cluster Software Component in the Available Updates page. The administrator can then select and apply the LCM framework update to upgrade it to the latest version2.

The administrator can perform an LCM inventory using Prism Element or Prism Central. The steps are as follows3:

• In Prism Element, go to the Network Configuration page and click Life Cycle Management.
• In Prism Central, go to the Services page and click Life Cycle Management.
• Click Inventory in the toolbar and select Perform Inventory from the drop-down menu.
• Wait for the inventory process to complete and check for any available updates.

The critical alerts listed are indicating that the default passwords are still in use for IPMI, the host, and the Controller Virtual Machine (CVM). This suggests that the passwords for these components were not changed from the default during the initial cluster configuration and deployment process, which is a critical security practice.

A. CVM password changes: The alert for the CVM using the default password indicates that the CVM password has not been changed. It is a standard security measure to change default passwords to prevent unauthorized access.

C. Host password changes: Similarly, the alert for the host using the default password indicates that the default password for the host has not been updated. This applies to the passwords used to access the hypervisor host directly.

Changing default passwords is a critical step in securing the Nutanix environment. This is highlighted in Nutanix's best practices and security guidelines, which recommend changing default passwords as part of the initial configuration to ensure that the environment is not left vulnerable to unauthorized access due to known default credentials. This process is typically part of the initial setup procedures outlined in the Nutanix documentation for cluster deployment and security configuration.

The IPMI alert also points to the need for changing default passwords, but since IPMI (Intelligent Platform Management Interface) is not specifically mentioned in the provided options, it falls under the broader category of host-level password changes, which would be covered by option C.

BIOS password changes (Option B) and Password policy changes (Option D) are also important but were not directly flagged by the alerts mentioned. BIOS password changes are usually a separate task and not indicated by the alerts given, while password policy changes are related to the policies governing password complexity and rotation rather than the initial password setup.

The issue described pertains to the inability to ping the IPMI IPs after moving the IPMI network links to the actual switches with specific VLAN configurations. The two changes that the administrator needs to make are:

A. SSH to AHV and set the VLAN ID using IPMI Tool: Since all VLANs are tagged in the new network configuration, the IPMI network interface needs to be aware of the VLAN it’s supposed to communicate on. This can be achieved by setting the VLAN ID using the IPMI Tool on the AHV.

C. SSH to AHV and change the IP address using IPMI tool: If the IPMI IP addresses were initially set in a different subnet that is not routable in the new network configuration, the administrator would need to change the IPMI IP addresses to match the new network configuration. This can be done by SSHing to the AHV and using the IPMI Tool to change the IP address.

According to the CPU (%) - VMware Docs web search result2, one of the possible causes of high CPU ready % is over-provisioning vCPUs for a VM or having too many VMs on a host. CPU ready % indicates the percentage of time that the VM was ready, but could not get scheduled to run on the physical CPU. High CPU ready % can lead to VM performance problems, such as slow response time or application latency. To improve VM performance, the administrator should reduce the number of vCPUs assigned to VMs or reduce the number of VMs on the hosts, so that there is less contention for CPU resources.