NCP-MCI-6.5 Nutanix Certified Professional - Multicloud Infrastructure (NCP-MCI) v6.5 exam Questions and Answers

According to the Troubleshoot high memory issues on Azure virtual machines web search result2, one of the common factors in a low memory situation is over-provisioning memory for a VM. Over-provisioning memory can cause memory pressure, which leads to swapping and degraded performance. Therefore, to fix this issue, the administrator should reduce the amount of memory assigned to the VM, based on the average hardware requirements for that operating system and application load.

Port 389 is the default port for LDAP without SSL encryption. Port 636 is used for LDAP over SSL (LDAPS). Port 3268 and 3269 are used for Global Catalog (GC) and Global Catalog over SSL (GCSSL), respectively2.

According to the Nutanix Volumes - Recommendations And Best Practices web search result3, two actions that the administrator should take when designing the Volume Group are:

• Distribute workload across multiple virtual disks: Use multiple disks rather than a single large disk for an application. Consider using a minimum of one disk per Nutanix node to distribute the workload across all nodes in a cluster. Multiple disks per Nutanix node may also improve an application’s performance. For performance-intensive environments, we recommend using between four and eight disks per CVM for a given workload.
• Enable RSS (Receive Side Scaling): Receive-side scaling (RSS) allows the system to use multiple CPUs for network activity. With RSS enabled, multiple CPU cores process network traffic, preventing a single CPU core from becoming a bottleneck. Enabling RSS within hosts can be beneficial for heavy iSCSI workloads. For VMs running in ESXi environments, RSS requires VMXNET3 VNICs. For Hyper-V environments, enable VMQ to take full advantage of Virtual RSS.

https://hyperhci.com/2019/07/22/nutanix-lcm-upgrade-process-failed-trouble-shooting/

According to the Nutanix Support & Insights web search result2, VM NICs on AHV can operate in two modes: Access and Trunked. Access NICs are the default, and allow one VLAN on the NIC. Trunked NICs allow multiple VLANs on a single NIC for VMs that are VLAN aware. If you must use trunked NICs, follow the steps described in the web search result2. Therefore, the most efficient way to have a VM on an AHV cluster with access to multiple VLANs is to update a vNIC on the VM to operate in trunked mode for all desired VLANs.

According to the Nutanix Community1, host maintenance mode is used to safely migrate all the user virtual machines (VMs) in the host and make sure no VMs are running on the node. If a VM can’t be migrated to another host, you need to shut down the VM for the host to enter into maintenance mode.

According to The Virtualist2, a storage container is a logical segmentation of a storage pool that can be mounted as an NFS datastore on ESXi hosts. You can choose a replication factor (RF) for each storage container, which determines how many copies of data are stored across different nodes.

 According to the Nutanix Support & Insights web search result1, the name of the internal bridge used by AHV nodes and CVMs is br0. The internal bridge is an Open vSwitch (OVS) bridge that connects the AHV host management interface, the CVM interface, and the VM vNICs. The internal bridge also acts as a gateway for the CVM and VM traffic to reach the external network through the host physical NICs.

The node is automatically re-imaged using the software currently running in the cluster. This is because Nutanix supports a feature called Auto Re-Image that allows adding nodes with different AOS versions to an existing cluster without manual intervention. The Auto Re-Image feature detects the AOS version mismatch and automatically downloads and installs the same AOS version as the cluster on the new node. This ensures that the cluster remains in a consistent state and avoids any compatibility issues.

One of the NICs needs to be configured on the internal VLAN. This is because the VMs that are isolated need to communicate with the firewall VM through a private network, and the firewall VM needs to communicate with the external network through a public network. The internal VLAN is a logical network that can be created and managed by AHV1. If the firewall VM does not have a NIC on the internal VLAN, it will not be able to route traffic between the isolated VMs and the outside world.

A constrained VM is one that does not have enough resources for the demand and can lead to performance bottlenecks. A VM is considered constrained when it exhibits one or more of the following baseline values, based on the past 21 days: CPU usage > 90% (moderate), 95% (severe) CPU ready time > 5%, 10% Memory usage > 90%, 95% Memory swap rate > 0 Kbps1. To provide adequate host resources, resize (increase) the constrained VMs1.

The correct answer is C. The VLAN was not created on the upstream switches.

A VLAN (virtual local area network) is a logical segmentation of a physical network that allows devices on the same VLAN to communicate with each other, regardless of their physical location. A VLAN also isolates the devices on different VLANs from each other, unless there is a router or a layer 3 switch that can route traffic between VLANs. To create a VLAN, the administrator needs to configure the network devices that are involved in the VLAN, such as switches, routers, and hosts. The administrator also needs to assign a unique VLAN ID to each VLAN, which is a number between 1 and 4094 that identifies the VLAN1.

In Nutanix AHV, the administrator can create a Nutanix managed network with a specific VLAN ID for guest VMs. This network can be assigned to VM NICs using Prism Element or Prism Central. However, creating a Nutanix managed network does not automatically create the VLAN on the upstream switches that connect the AHV hosts. The administrator needs to manually configure the upstream switches to allow the VLAN traffic on the ports that connect to the AHV hosts. The administrator also needs to ensure that the upstream switches are interconnected physically or virtually and can forward traffic between different VLANs if needed2.

Therefore, if an administrator has created a Nutanix managed network with a VLAN ID of 512 and notices that the VMs on that network can only communicate with other VMs on the same host, but not with VMs on different hosts in the cluster, the most likely cause of this issue is that the VLAN was not created on the upstream switches. This means that the switches are dropping or blocking the traffic with VLAN ID 512 and preventing it from reaching other hosts or VMs. To resolve this issue, the administrator should create the VLAN on the upstream switches and allow it on the ports that connect to the AHV hosts3.

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'.

Prism Element and NCC are two ways to run all NCC checks manually on a Nutanix cluster. Prism Element is the web console that provides management and monitoring capabilities for a single Nutanix cluster. Prism Element has a Health dashboard that shows the status of various components and services in the cluster, such as disks, nodes, CVMs, NCC, and alerts. The Health dashboard also allows the administrator to run NCC checks manually by using the Actions drop-down menu on the right side of the screen. The administrator can choose to run all NCC checks or specific checks based on the category or severity. The NCC checks will run in the background and generate a report that can be viewed or downloaded from the Summary tab. This method is easier and faster than running NCC from the command line on the CVM.

NCC stands for Nutanix Cluster Check, which is a framework of scripts that performs system checks and validations on Nutanix clusters. NCC can detect issues related to hardware, software, configuration, hypervisor, networking, and more. NCC can be run from the command line interface (CLI) of any CVM in the cluster by using the ncc command. To run all NCC checks manually, the administrator can use the command ncc health_checks run_all, which will execute all available checks and display the results on the screen. This method is more comprehensive and detailed than running NCC from Prism Element.

References: : [Health Dashboard - Prism Element Guide] : [Nutanix Cluster Check (NCC) - Nutanix Support & Insights] : [Running NCC Checks - Nutanix Support & Insights]

According to section 4 of the exam blueprint guide1, one of the topics covered is AHV networking components and configuration settings. One of these components is Open vSwitch (OVS), which is a software switch that provides network connectivity between VMs and physical networks. OVS has two types of ports:

• Uplink ports: These are physical ports that connect to external networks or switches.
• Internal ports: These are virtual ports that connect to VMs or other internal networks.

To view the uplink state of all AHV nodes in the cluster, an administrator can use the manage_ovs command with the show_uplinks option. This command displays information such as port name, link state, speed, duplex mode, MTU size, bond mode, and bond status. However, this command only works on a single node. To run the command on all nodes in the cluster, an administrator can use the allssh command, which executes a command on all CVMs in parallel. Therefore, the correct command is:

allssh manage_ovs show_uplinks

According to the web search results, three storage optimizations that should be set on a dedicated storage container for a VDI solution with persistent desktops are compression, deduplication and erasure coding. Compression is a technique that reduces the size of data by removing redundant information. Deduplication is a technique that eliminates duplicate copies of data blocks and stores only unique blocks. Erasure coding is a technique that increases usable capacity by reducing the replication factor of data blocks and using parity information instead7. These three optimizations can improve performance and save storage space for VDI workloads, especially during a node failure event when data needs to be rebuilt from parity information8. The administrator can enable these optimizations by using Prism Element web console or ncli command-line interface9.

Terminology

• Availability Zone – it is represented by all resources (Nutanix Clusters) connected to Prism Central or Xi Leap Availability zone. Depends on the architecture, Availability zone can represent geographic territory, datacenter or server room in the datacenter. Protection policies – in protection policies you set up (RPO, Retention), rules to auto-apply policies to virtual machines

https://vmware mine.com/2019/02/08/nutanix-leap-runbooks-part-1/#sthash.VwrzSzhQ.dpbs

According to the web search results, a consistency group is a group of related applications or services that must be recovered together in order to work properly, and this means more than being recovered at the same time67. They also typically need to be recovered to the same point in time6. Therefore, to meet the requirement of protecting all VMs of a multi-tier application at the same time, the administrator must create a consistency group for the application and place all VMs in it8. This way, the administrator can apply data protection policies and schedules to the entire consistency group as a single unit8.

An Application Security Policy is a security feature in Nutanix AHV that can be used to restrict network communication between virtual servers based on a variety of criteria, such as IP address, port, and protocol. By creating a policy that restricts communication to authorized hosts and applying it to the servers in enforce mode, the administrator can prevent unauthorized communication between virtual servers.

https://www.nutanix.com/products/ahv

According to the Nutanix 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.

A bully VM is a VM that consumes too many resources and causes other VMs to starve. A bully VM can affect the performance and availability of other VMs on the same host or cluster by hogging CPU, memory, disk, or network resources. A bully VM can be identified by using the VM Profile feature in Prism Central2. 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 follows3:

• 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.

To identify a bully 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.

According to section 5 of the exam blueprint guide1, one of the topics covered is live migration. Live migration is the process of moving a running VM from one host to another without any downtime or interruption of service. To perform live migration, there are some prerequisites that must be met, such as:

• All AHV hosts have IP addresses in the same subnet
• All VMs are configured for the same VLAN
• The source and destination hosts have enough resources to accommodate the VM
• The VM does not have any PCI devices attached

Answer: A. VM-VM anti-Affinity policy

A VM-VM anti-Affinity policy is a rule that ensures that two or more VMs don’t run on the same AHV host. It’s useful when an application provides HA and an AHV host can’t be an application’s single point of failure1. In this case, the SQL cluster VMs should have a VM-VM anti-Affinity policy configured to prevent them from running on the same host and causing an outage if that host fails. A VM-VM anti-Affinity policy can be created using the aCLI commands2. The other options are not relevant for this scenario.

References: 1: Affinity Policies - Nutanix Support & Insights 2: Affinity Policies Help | Nutanix Community

According to the web search results, the two impacts on the cluster that will result from increasing the vCPU count on all of the VDI VMs are:

• Increase CPU utilization%: CPU utilization is the percentage of time that a CPU is busy executing instructions5. By increasing the vCPU count on all of the VDI VMs, the administrator will increase the demand for CPU resources on the cluster, which will increase the CPU utilization percentage6.
• Increase CPU ready%: CPU ready is the percentage of time that a vCPU is ready to run but is waiting for a physical CPU to become available5. By increasing the vCPU count on all of the VDI VMs, the administrator will increase the contention for physical CPU resources on the cluster, which will increase the CPU ready percentage6. A high CPU ready percentage can indicate performance issues such as latency or slowdowns5.

CloudInit is a package that contains utilities for early initialization of cloud instances. It allows you to customize virtual machines provided by a cloud vendor by modifying the generic OS configuration on boot. You can use CloudInit to set the OS hostname, add custom users, add keys, run custom scripts, and more2. CloudInit is supported by most major Linux and FreeBSD operating systems and works across different cloud platforms3. Sysprep is a tool for Windows operating systems that prepares an installation for cloning, auditing, and customer delivery4.

References: 1: Replacing Nodes in Nutanix Cluster - Nutanix Support & Insights 2: Customize a Linux VM with cloud-init in Azure - Azure Virtual Machines 3: Cloud-Init - The standard for customising cloud instances 4: Sysprep (Generalize) a Windows installation

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.

According to the Nutanix Prism Element Guide, Prism Element uses a single SSL certificate on a Nutanix cluster. The certificate is used to secure the communication between the web browser and the Prism web console. The certificate is also used to authenticate the cluster to external services, such as Active Directory, SMTP, and SNMP. The certificate can be either self-signed or signed by a trusted certificate authority (CA). The certificate can be replaced or renewed through the Prism web console or the ncli command-line interface.

Answer: D. Load the Virtual SCSI pass-through controller.

The error message shown in the image indicates that Windows 10 setup cannot find any drives to install the OS. This is because the Nutanix AHV hypervisor uses a virtual SCSI pass-through controller to present disks to the VMs, and Windows 10 does not have a built-in driver for this device. Therefore, the administrator needs to load the Nutanix VirtIO driver for the virtual SCSI pass-through controller during the OS installation process. The Nutanix VirtIO driver package contains various drivers that are specifically used by Windows VMs hosted in the Nutanix environment to enhance their stability and performance1. The administrator can download the latest Nutanix VirtIO driver package from the VirtIO downloads page of the Nutanix support portal. The administrator can then follow these steps to load the driver and install the OS2:

• On the Windows 10 setup screen, click Load driver.
• Insert a USB drive or mount an ISO image that contains the Nutanix VirtIO driver package.
• Browse to the location of the driver package and select the folder that matches the OS architecture (32-bit or 64-bit).
• Select the vioscsi.inf file and click Next.
• Wait for the driver to load and then click Refresh.
• Select the disk where you want to install Windows 10 and click Next.

References: 1: VirtIO Driver Versions for Windows 2: Installing Windows on AHV

"Playbook allows you to define a trigger that results in the execution of an action or a series of actions. A trigger may be an event that occurs in the system, such as an alert or a request made by you. The resultant actions that you configure can be VM actions, communication actions, alert actions, or report actions." https://portal.nutanix.com/page/documents/details?targetId=Intelligent-Operations-Guide-vpc_2023_3:ssp-report-management-ssp-pc-c.html#:~:text=The%20environment%20summary%20report%20provides,is%20registered%20to%20Prism%20Central.

One of the possible reasons for a cluster to transition out of NearSync is insufficient network bandwidth between the source and target clusters. NearSync requires a minimum network bandwidth of 10 Mbps per VM for replication3. If the network bandwidth is lower than the required amount, the replication of recovery points may take longer than the configured RPO, resulting in an Out of NearSync condition. To address this issue, you can increase the network bandwidth between the clusters or reduce the number of VMs protected by NearSync4.

References: 1: Stargate - Nutanix Bible 2: Nutanix Cluster Architecture Overview - Nutanix Bible 3: NearSync Disaster Recovery (RPO <= 15 minutes) - Nutanix Support & Insights 4: Transitioning in and out of NearSync - Nutanix Support & Insights

According to the web search results, the most efficient action an administrator should take to ensure a supported state when adding a node with a higher AOS release to an existing cluster is to perform a standalone reimage of the new node and then add it to the cluster1. This way, the new node will have the same AOS version as the existing nodes, and there will be no compatibility issues or downtime. Therefore, option C is correct, while options A, B, and D are not.

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

According to the Nutanix Prism Central Guide, to configure a syslog server in Prism Central, you need to specify the transport protocol (TCP or UDP) and the IP address/port of the syslog server.

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.

Stargate is the AOS process that handles all I/O operations for the cluster. It is responsible for determining whether an I/O from a user will be written to the OpLog or to the Extent Store, based on the type and size of the I/O. Stargate also performs data tiering, compression, deduplication, and erasure coding1. Stargate runs on every CVM and communicates with other Stargates to ensure data locality and redundancy2.

This will allow the administrator to quickly identify VMs that are overprovisioned or underutilized based on their performance metrics.

https://www.nutanix.com/support-services/training-certification/certifications/certification-details-nutanix-certified-professional-multicloud-infrastructure-6_5

VirtIO drivers are device drivers that are specifically designed for virtualized environments. They allow the guest operating system to communicate directly with the underlying hardware, bypassing the emulation layer. This improves the performance and efficiency of the virtual machines. VirtIO drivers are supported by various hypervisors, including Nutanix AHV1.

Nutanix AHV uses SCSI disks for VMs by default. However, Windows does not have native support for SCSI disks and requires VirtIO drivers to recognize them. Therefore, if an administrator is installing Windows 2019 on a new VM on an AHV cluster, they need to install the VirtIO drivers before selecting the destination disk for the installation. Otherwise, they will not see any drives listed for the install2.

To install the VirtIO drivers during Windows installation, the administrator can use one of the following methods3:

• Use a VirtIO ISO image that contains the driver files. The administrator can download the VirtIO ISO image from the Nutanix support portal and upload it to the AHV image service. Then, they can attach the VirtIO ISO image to the VM as a CD-ROM device and load the driver from it during Windows installation.
• Use a Nutanix Guest Tools (NGT) ISO image that contains the driver files and other tools. The administrator can download the NGT ISO image from Prism Element or Prism Central and attach it to the VM as a CD-ROM device. Then, they can load the driver from it during Windows installation.
• Use a floppy disk image that contains only the driver files. The administrator can create a floppy disk image using tools such as WinImage or WinRAR and upload it to the AHV image service. Then, they can attach the floppy disk image to the VM as a floppy device and load the driver from it during Windows installation.

To periodically send information about cluster efficiency via email to a set of users, the administrator can follow these steps:

• Create a report in Prism Central that contains the relevant information about cluster efficiency.
• Add a schedule to the report to generate and send the report via email to the set of users at a specified frequency.

This will ensure that the users receive regular updates about the cluster efficiency without the need for manual intervention.

The cluster time zone is a setting that determines the time zone used by all CVMs in the cluster. The cluster time zone affects the timestamps of Nutanix logs, events, alerts, and reports. The cluster time zone also affects the scheduling of tasks such as snapshots, replication, and upgrades. By default, the cluster time zone is set to UTC (Coordinated Universal Time) when the cluster is created3.

To change the cluster time zone, the administrator needs to use the ncli (Nutanix command-line interface) on any CVM in the cluster. The steps are as follows4:

• Log in to any CVM using SSH.
• Run ncli cluster get-timezone to check the current cluster time zone.
• Run ncli cluster set-timezone timezone= to change the cluster time zone, where  is a valid time zone identifier (for example, America/New_York).
• Run ncli cluster get-timezone again to verify that the cluster time zone has been changed.

Note that changing the cluster time zone does not affect the time zone of Prism Element or Prism Central VMs. To change their time zone, the administrator needs to use Prism Element UI or Prism Central UI respectively5.