Nutanix Updated NCS-Core Exam Questions and Answers by miya

To verify that a Nutanix cluster can tolerate a single-node failure, the consultant should use the command nutanix@cvm~$ ncli cluster get-domain-fault-tolerance-status type=node. This command is executed from the Controller Virtual Machine (CVM) and checks the cluster's fault tolerance status specifically for node failures, providing insights into how the cluster's data resiliency and redundancy configurations are holding up against potential single-node failures.References: Nutanix CLI Guide, Nutanix Fault Tolerance Documentation.

For the Exchange VM experiencing I/O performance issues, the recommended storage optimization change is Option A, "No data reduction." Exchange, as an application, is highly sensitive to latency and typically does not benefit significantly from data reduction technologies like deduplication or compression, which can introduce additional processing overhead and potentially worsen performance issues.

By configuring the container for Exchange with no data reduction, the system maximizes I/O performance by eliminating any additional processing that could delay data access. This setup ensures that Exchange has the fastest possible access to its data, which is crucial for its performance.

References:This recommendation aligns with best practices for Exchange storage on Nutanix, as detailed in the Nutanix best practices guide for deploying Microsoft Exchange, where it advises against using data reduction features for databases requiring high I/O throughput.

In a Nutanix cluster, I/O latency can be affected by several factors. Given the scenario where a 32-node hybrid cluster is experiencing I/O latency, one possible cause could be the Information Life Cycle Management (ILM) constantly moving data due to curator scans1.

In a Nutanix cluster, ILM is responsible for managing data placement across different storage tiers. It promotes frequently accessed data to higher-performance tiers (like SSDs) and demotes less frequently accessed data to lower-performance tiers (like HDDs)1. This process involves moving data around, which can cause I/O operations to take longer, leading to increased latency1.

If the working set size (WSS) exceeds the SSD tier capacity, ILM will have to constantly move data between the SSD and HDD tiers to accommodate new data. This constant data movement can lead to increased I/O latency1.

Therefore, if curator scans caused by ILM are constantly moving data, it could be the reason for the observed I/O latency in this scenario.

References:

• Disk I/O Latency on a Nutanix Cluster | Nutanix Community
• Nutanix Volumes - Recommendations And Best Practices
• Nutanix Support & Insights
• Expand Cluster with Nodes with Higher NIC SPEED (25 GBPS) | Nutanix …
• [Scaling Up VM Storage Performance on AHV – Volume Group … - Nutanix]
• [About support for Nutanix segmented iSCSI network | Managing AHV …]

Ref: https://next.nutanix.com/community-blog-40/scaling-up-vm-sto rage-performance-on-ahv-volume-group-load-balancer-28063