NCP-MCI-6.5 Sample Questions Answers

According to the Red Hat Customer Portal, to use RELP with Rsyslog, you need to install the rsyslog-relp package on both the server and the client. If the remote server does not have rsyslog-relp installed, RELP logging will not work as expected.

According to the Nutanix Prism Central Guide, Prism Central allows you to apply storage policies on a per VM basis using Category, so that the VM uses the storage configuration defined in the storage policy. Using a storage policy, you can manage parameters of VMs, such as encryption, type of or lack of data compression, and IOPS or Throughput throttling values to be applied to the entities.

According to the image description, the exhibit shows a screenshot of a computer screen with a table of data. The table has 6 columns and 4 rows. The columns are labeled “Date”, “Time”, “Status”, “Details”, “Configuration”, and “Duration”. The rows contain information about different configurations and their statuses. The background is a light blue color. There is a pop-up message on the bottom right corner of the screen that reads “This question has been answered. Click here to enable the edit button.”

Based on the table data, it seems that the screenshot is taken from the Prism Central web console, showing the results of a cluster health check report. The report shows that there are four failed checks: Host Password Policy, CVM Password Policy, NTP Configuration, and Cluster Time Skew2. These checks indicate that some initial cluster configuration tasks were missed during the deployment process.

The Host Password Policy check verifies that the host passwords are not set to default values and are compliant with the password policy defined in Prism Central3. The CVM Password Policy check verifies that the CVM passwords are not set to default values and are compliant with the password policy defined in Prism Central4. These checks are important for ensuring the security and compliance of the cluster. Therefore, changing the host and CVM passwords from their default values and following the password policy guidelines are two initial cluster configuration tasks that were missed.

References: 1: VM Details View - Nutanix Support & Insights 2: Cluster Health - Nutanix Support & Insights 3: Host Password Policy - Nutanix Support & Insights 4: CVM Password Policy - Nutanix Support & Insights

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.

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.

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.

NGT is a software package that enables advanced VM management features provided by Nutanix, such as file-level restore, VM mobility, and application-consistent snapshots12. To use NGT, you need to enable the NGT feature for a VM in the Prism Element web console, mount the NGT installer (ISO disk file) in the VM, and install NGT in the VM1. However, before installing NGT, you need to ensure that the VM can communicate with the NGT-Controller VM service, which runs on the Controller VM (CVM) of each Nutanix node3. The NGT-Controller VM service listens on port 9943 for incoming requests from the guest VMs3. Therefore, you need to enable port 9943 on the ESXi-hosted VM to allow communication with the NGT-Controller VM service.

Virtual NIC receive packet dropped is the most useful VM metric for isolating the cause of users being disconnected from remote desktop sessions to a specific VM. This metric shows the number of packets that are dropped by the virtual NIC of the VM due to insufficient buffer space or other reasons. Packet drops can indicate network congestion, misconfiguration, or performance issues that can affect the quality and availability of remote desktop sessions. Packet drops can also cause retransmissions, delays, and errors in TCP-based protocols such as RDP2. To view this metric in Prism, go to Entities > Compute & Storage > VMs > Summary View and select a VM. Then, in the Details View, go to Metrics > Performance and select Virtual NIC receive packet dropped from the drop-down menu3.

The best way for the administrator to configure Prism to send encrypted messages to a set of recipients is to set the SMTP Security Mode to STARTTLS. This will ensure that all messages sent over SMTP are encrypted and secure. Additionally, the administrator should consider installing SSL certificates on Prism Central to ensure that the messages are being sent securely. Finally, the administrator should consider configuring Prism Central to use Cluster Lockdown, which will help ensure that the messages are only sent to the intended recipients.

A GPU (graphics processing unit) is a specialized hardware device that can accelerate graphics rendering and computation for applications that use APIs such as DirectX, OpenGL, CUDA, and OpenCL. A GPU can also offload the CPU from encoding and decoding tasks for remote display protocols such as Frame Remote Desktop Protocol (FRP). A VM can use a GPU either by directly accessing a physical GPU (pGPU) on the host or by using a virtual GPU (vGPU) that shares a pGPU with other VMs. A user running a computer aided design (CAD) application may benefit from using a GPU or a vGPU to improve the performance and responsiveness of the application, especially when moving windows or rendering images. However, if the GPU or vGPU is not properly configured or provisioned, the user may experience slow response time within the VM. Therefore, to diagnose the problem, the administrator should monitor the GPU Usage metric for the VM. The GPU Usage metric shows the percentage of GPU resources that are consumed by the VM over time3. The administrator can use Prism Central to view the GPU Usage metric for each VM in a chart or a widget4. The administrator can also use Prism Central to view other metrics related to GPU performance, such as GPU Memory Usage, GPU Encoder Usage, and GPU Decoder Usage3. By analyzing these metrics, the administrator can determine if the VM is using the GPU efficiently and optimally, or if it needs more or less GPU resources.

"An administrator has been tasked with increasing security on Nutanix cluster by disabling password authentication when accessing the CVM and AHV hosts and instead moving to key-based SSH, What is the easiest way for the administrator to meet these needs? Enable Cluster Lockdown and provide an RSA key."

 Cluster Lockdown mode disables password authentication when accessing the CVM and AHV hosts and instead requires key-based SSH. To enable Cluster Lockdown mode, you need to provide an RSA key.

Therefore, by enabling Cluster Lockdown mode and providing an RSA key, you can increase security on Nutanix cluster by disabling password authentication when accessing the CVM and AHV hosts and instead moving to key-based SSH with minimal effort.

https://next.nutanix.com/how-it-works-22/streamlined-login-and-increase-security-key-based-ssh-login-37397

Data locality is the capability of storing VM data on the node where the VM is running and ensuring that the read I/O does not have to traverse the network. Data locality is a unique feature of Nutanix that provides high performance and low latency for VMs by minimizing network traffic and crosstalk. Data locality works by writing one copy of the data local to the VM and the other copy (or copies) on other nodes. When a VM migrates to another node, Nutanix also moves its data to the new node and serves all I/O requests locally. Data locality also adapts to changing workloads and access patterns by dynamically moving data to where it is needed most1.

The best way to fix this issue is to increase the amount of memory assigned to the VM from the Prism web console. This option allows the administrator to modify the VM configuration without accessing the CVM or shutting down the VM. The Prism web console provides a simple and intuitive interface for managing Nutanix clusters and VMs1. To change the memory allocation for a VM, the administrator can follow these steps2:

• Go to the VM dashboard
• Select the VM from the VMs list
• Choose Update
• Adjust the amount of memory assigned to the VM
• Click Save

These are the three steps that the administrator must take to increase throughput to the host. According to the network diagram, the host has two 10Gb interfaces and two 1Gb interfaces in the default bond, but only one of the 10Gb interfaces is connected to a switch. The other 10Gb interface is disconnected and has a red “X” on it. The two 1Gb interfaces are also disconnected and have dotted lines. This means that the host is using only one 10Gb interface for all its network traffic, which limits its maximum bandwidth to 10 Gbps.

To increase the throughput, the administrator should connect both 10Gb interfaces to the physical switch, preferably to different switches for redundancy and high availability. This will allow the host to use both 10Gb interfaces for network traffic, which can increase its maximum bandwidth to 20 Gbps. However, this also requires changing the bond mode from active-backup to balance-slb or balance-tcp, which are load balancing modes that distribute network traffic across multiple interfaces based on source MAC address or TCP session1. The default bond mode of active-backup only uses one interface at a time and switches to another interface only when the active one fails2.

Finally, the administrator should remove any 1Gb interfaces still connected from the default bond, as they are not needed and may cause performance issues or conflicts with the load balancing modes. The 1Gb interfaces can be used for other purposes, such as management or backup networks, by creating separate bonds or bridges for them3. Alternatively, they can be left disconnected if they are not required.

According to the Dell Unity: Data Reduction Technical White Paper1, snapshots and clones on Dell Unity use the Copy-on-Write (CoW) algorithm to maximize efficiency and effectiveness. CoW is a technique that defers the copying of data until it is modified. This means that snapshots and clones only consume space when changes are made to the source or the clone, respectively. CoW also preserves the original data in case of a rollback or recovery operation.

 When a node with Erasure Coding fails, the cluster will automatically rebuild the missing data using replication factor (RF) 2 or 3, depending on the cluster configuration. This means that the data that was previously stored using Erasure Coding will now be stored using full copies, which may increase the amount of data stored in the SSD tier1.

https://portal.nutanix.com/page/documen ts/details/?targetId=Prism-Central-Guide-Prism-v510:mul-alert-policies-user-defined-configure-pc-c.html

According to the Nutanix Support & Insights web search result3, shadow clones are vDisk copies that are created by the cluster when a vDisk is read by multiple VMs. Shadow clones are immutable copies of a vDisk that are stored in different nodes in the cluster, and are used to improve read performance and reduce network traffic. Shadow clones are automatically created and deleted by the cluster, based on the demand and availability of resources.

https://portal.nutanix.com/page/documents/details?targetId=Prism-Central-Guide-vpc_2023_3:mul-cluster-storage-policy-pc-c.html

API Explorer page will launch when an administrator presses the letter A on the keyboard after logging into Prism Element. This is one of the keyboard shortcuts that Prism Element provides for accessibility and ease of use1. API Explorer is a tool that allows users to explore and test Nutanix REST APIs within Prism Element1.

https://www.nutanixbible.com/3b-book-of-prism-navigation.html

According to the web search results, the cluster redundancy factor (RF) determines how many copies of the cluster metadata and configuration data are stored on different nodes. By default, the cluster RF is 2, which means that there are three copies of the Zookeeper and Cassandra data on the cluster. If the cluster RF is increased to 3, then there will be five copies of the Zookeeper and Cassandra data on the cluster12. This means that the Zookeeper component can tolerate two failures, as it can still operate with a quorum of three nodes out of five3.

However, the container replication factor (RF) determines how many copies of the VM data and oplog are stored on different nodes. The container RF can be set independently for each container, and it can be different from the cluster RF. For example, a container can have RF 2 even if the cluster has RF 34. In this case, the container will only have two copies of the VM data and oplog on the cluster, regardless of the cluster RF. This means that the Extent Groups component can only tolerate one failure, as it needs at least one copy of the VM data and oplog to be available5.

Therefore, if the administrator increases the cluster RF to 3, but does not modify the containers, then the new values in the data resiliency dashboard will be Zookeeper = 2 and Extent Groups = 1.

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

Nutanix leverages a method for determining the bands called ‘Generalized Extreme Studentized Deviate Test’. A simple way to think about this is similar to a confidence interval where the values are between the lower and upper limits established by the algorithm.

Another web source3 shows an example of how anomaly detection works in Nutanix Prism Central. In the video, you can see that when the observed value of a metric deviates significantly from the predicted value based on historical data, an anomaly event is triggered and displayed on a chart.

Therefore, by comparing the observed values with the predicted values based on historical data, Nutanix anomaly detection can identify abnormal behavior and alert you accordingly.

network segmentation on Nutanix clusters refers to creating a separate network for service-specific communication and isolating different types of traffic over selected VLANs or physical interfaces.

https://next.nutanix.com/ncm-intelligent-operations-formerly-prism-pro-ultimate-26/network-segmentation-isolating-service-specific-traffic-39463

https://next.nutanix.com/how-it-works-22/network-segmentation-basics-38414

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 agent VM is a special type of VM that is used for running services or applications that are not affected by high availability (HA) events or host maintenance. An agent VM is never migrated to any other host in the cluster. If an HA event occurs or the host is put in maintenance mode, agent VMs are powered off and are powered on on the same host once that host returns to a normal state. This behavior is different from regular VMs, which are migrated to another host in the cluster if possible, or restarted on the same host if not possible1.

Therefore, during an AHV upgrade, an administrator may find that a critical VM was powered off rather than migrated to another host if the VM was marked as an agent VM. This can be done either from the Prism web console by selecting the Use this VM as an agent VM option in the Update VM dialog box, or from the aCLI by using the vm.create or vm.update commands with the agent_vm=true parameter2. To avoid this situation, the administrator should ensure that any critical VMs are not marked as agent VMs before starting the AHV upgrade.

https://portal.nutanix.com/page/documents/details/?targetId=Web-Console-Guide-Prism-v51:wc-block-services-c.html

https://portal.nutanix.com/page/documents/details/?targetId=Web-Console-Guide-Prism-v50:wc-bl ock-services-enabling-t.html

Provision storage on the Nutanix cluster by creating a volume group. Create a client whitelist to enable access to the volume group by using the IP addresses or client initiator IQNs in a whitelist (as part of the volume group configuration). Create a secret for the volume group if you are using CHAP authentication.

According to the web search results, Prism Central is a multi-cluster manager that provides a single, centralized management interface for Nutanix environments12. One of the features of Prism Central is multi-cluster Single Sign On (SSO), which allows users to log in once and access multiple clusters without re-entering credentials3.

Automated live migration is a feature of Nutanix that allows the cluster to automatically move VMs from one host to another without any downtime, in order to optimize the performance and availability of the cluster. According to the Nutanix documentation1, automated live migration can occur in the following scenarios:

• Cluster resource hotspot: When a host or a group of hosts experience high resource utilization, such as CPU, memory, or network, the cluster can automatically migrate some VMs to other hosts with lower utilization, in order to balance the load and avoid performance degradation.
• AOS upgrade: When upgrading the Nutanix software (AOS), the cluster can automatically migrate the VMs from the host that is being upgraded to another host in the same availability zone, in order to maintain the VM availability and minimize the impact of the upgrade process.
• AHV host maintenance mode: When putting an AHV host into maintenance mode, the cluster can automatically migrate all the VMs from that host to another host in the same availability zone, in order to prepare the host for maintenance operations such as hardware replacement or firmware update.

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 correct answer is C. Network latency.

The diagram shows a solution that uses synchronous replication between two remote protection domains, cluster site A and cluster site B. Synchronous replication is a feature that allows near-zero RPO (recovery point objective) by replicating data to the remote site before acknowledging writes to the local site. However, synchronous replication has some requirements and limitations that must be met for it to work properly. One of these requirements is that the network latency between the two sites must be less than or equal to 5 ms1. If the network latency is higher than 5 ms, the synchronous replication will fail and the protection policy will be suspended2.

Therefore, based on the diagram, the most likely cause of the issue is that the network latency between cluster site A and cluster site B is higher than 5 ms, which prevents the synchronous replication from working. To verify this, the administrator can use the “ncli cluster ping” command to measure the network latency between the two sites3. If the network latency is indeed higher than 5 ms, the administrator can either improve the network performance or switch to a different replication mode, such as near-synchronous or asynchronous.

when you create a custom alert policy, you can choose between two types of thresholds: Static Threshold and Behavioral Anomaly. Static Threshold allows you to set a fixed value for the metric that triggers the alert. Behavioral Anomaly allows you to use machine learning to detect abnormal behavior based on historical data.

If you select Behavioral Anomaly as the threshold type, you cannot set a warning level for the alert. You can only set a critical level that indicates how much deviation from normal behavior is considered an anomaly3. Therefore, the Alert warning if field is greyed out when you select Behavioral Anomaly.

Configure VM-Host affinity for the nodes that meet the application’s GPU requirement. This is because VM-Host affinity allows the administrator to specify which nodes a VM can run on or must not run on1. By creating a VM-Host affinity rule that binds the application VM to the three nodes that have the physical GPU, the administrator can ensure that the VM will always run on a node that meets its requirement, regardless of any HA or migration events. This also allows the other nodes in the cluster to host other VMs without any restrictions.

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.

The correct answer is B. The existing and the expansion node are on different VLANs.

The output shows that the new node has a br0-up bond with four interfaces: eth0, eth1, eth2, and eth3. The bond is configured with LACP active and LACP fallback set to false. This means that the bond will only work if the upstream switch supports LACP and is configured to form an LACP group with the four interfaces. However, the output also shows that the bond has no IP address assigned to it, which indicates that the bond is not operational. One possible reason for this is that the existing and the expansion node are on different VLANs, and the upstream switch is not configured to allow the VLAN traffic on the LACP group. This would prevent the new node from communicating with the cluster and being discovered by the Expand Cluster function in Prism.

To verify this, the administrator can check the VLAN configuration on the upstream switch and compare it with the existing nodes. Alternatively, the administrator can use the “manage_ovs show_uplinks” command on an existing node and compare the output with the new node. If there is a VLAN mismatch, the administrator can either change the VLAN configuration on the switch or on the new node to match the existing nodes.

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.

According to the web search results, one of the requirements for cross-hypervisor disaster recovery (CHDR) is to install and configure Nutanix Guest Tools (NGT) on all the VMs2. NGT configures the VM with all the required drivers for VM portability. Without NGT, the VMs may fail to boot after being migrated to a different hypervisor type. 

Nutanix provides two types of granular RBAC for AHV hosts: category based and cluster based3. Category based RBAC allows administrators to assign roles to users or groups based on categories, which are key-value pairs that can be applied to various entities in Prism Central, such as clusters, hosts, VMs, images, and networks. Categories can be used to group entities by different criteria, such as department, project, environment, or location. For example, an administrator can create a category key named Department and assign different values to it, such as Finance, Marketing, or Engineering. Then, the administrator can apply this category to different clusters or hosts and assign roles to users or groups based on this category. This way, users or groups can have different levels of access to different clusters or hosts depending on their department4.

Cluster based RBAC allows administrators to assign roles to users or groups based on specific clusters registered in Prism Central. For example, an administrator can create a role named Cluster Admin and assign it to a user or group for a particular cluster. This way, the user or group can have full access to that cluster and its hosts and VMs, but not to other clusters5.

Curator is the process that runs on every node in a Nutanix cluster and is responsible for data management tasks such as deduplication, compression, erasure coding, and replication factor compliance. Curator also handles disk failure recovery by scanning Cassandra to find all data previously hosted on the failed disk, and all disks in that node. Curator then rebuilds the data on other nodes in the cluster using the distributed storage fabric1.

According to the web search results, one possible cause of inter-VM communication failure between hosts is that the switch is not configured to allow VLAN 15 traffic. VLAN 15 is the default VLAN ID used by AHV for internal communication between CVMs and hosts. If the switch blocks or drops VLAN 15 packets, it will prevent inter-VM communication across hosts4. To enable full inter-VM communication, the administrator should update the switch to specifically allow VLAN 15 traffic on the ports connected to the AHV hosts.