NS0-521 Exam Dumps - Netapp NCIE SAN ONTAP Questions and Answers

When a LUN shows 90% used space in the NetApp ONTAP CLI but a Windows Server shows only 10% used space, the discrepancy is often due to how space allocation is handled between the two systems. Enabling space allocation ensures that the ONTAP system accurately reflects the actual space usage as reported by the host system, in this case, the Windows Server. This adjustment allows ONTAP to reclaim and manage space more effectively, aligning the reported usage between the ONTAP system and the host.

For more information, refer to:

NetApp Community Discussion on Space Allocation

NetApp Documentation on Space Usage

For a NetApp AFF All SAN Array (ASA) A800 MetroCluster IP configuration with 72 disks per site and Cisco N9K-C9336C-FX2 backend switches, the minimum number of rack units required on each site is 16 RU. This includes space for the controllers, disk shelves, and the necessary network switches. This configuration ensures that all components are properly accommodated and operational within the specified rack space.

For detailed information on the rack unit requirements and MetroCluster IP configurations, refer to:

NetApp Documentation on MetroCluster IP

MetroCluster IP Solution Architecture

To concurrently serve a namespace over NVMe/FC, a LUN over FCP, a LUN over iSCSI, and an NFS export, only one data SVM (Storage Virtual Machine) is required. NetApp ONTAP allows a single SVM to supportmultiple SAN and NAS protocols simultaneously, enabling efficient and consolidated management of storage resources.

For more information, refer to:

NetApp Documentation on SVM Configuration

NetApp SVM Best Practices

To enable CHAP (Challenge-Handshake Authentication Protocol) authentication on iSCSI sessions, the command vserver iscsi security create should be used. This command sets up the necessary security policies and passwords required for CHAP authentication, ensuring secure access to iSCSI targets.

For more details, refer to:

NetApp Documentation on iSCSI Configuration​ (NetApp)​.

For enabling jumbo frames on Cisco Nexus switches for NVMe over TCP with tagged VLANs, the following changes are required:

Modify the Cisco Nexus switches to use an MTU of 9216: Setting the MTU to 9216 ensures that the network can handle jumbo frames, reducing the number of packets needed for large data transfers and thus improving performance.

Modify the appropriate broadcast domain in NetApp ONTAP software to use an MTU of 9216: This setting must match the network configuration to ensure end-to-end support for jumbo frames, which is essential for optimizing performance in NVMe over TCP environments.

For additional information, refer to:

NetApp Documentation on NVMe over TCP

Cisco Documentation on Jumbo Frames

To verify that a modified FC port is usable after it has been repurposed from tape backup to FCP SAN, the command system node hardware unified-connect show should be used. This command checks the status and configuration of the unified connect hardware, ensuring that the port is correctly set up for the new function in the SAN environment.

For additional details, see:

NetApp Command Reference

The likely cause for the disappearance of all snapshots after a ransomware attack that encrypted all files on the LUN is the Snapshot autodelete feature. When the volume becomes full due to the encryption, the autodelete feature removes older snapshots to free up space, preventing the volume from running out of space and ensuring write operations can continue.

For more information, see:

NetApp Documentation on Snapshot Autodelete

NetApp Community Discussion on Snapshot Deletion

When adding 40 more hosts to a two-node NetApp ONTAP cluster that is already hosting 64 SAN hosts, the following actions are necessary to avoid potential performance problems:

Configure additional FC target ports: Increasing the number of Fibre Channel (FC) target ports on the storage nodes will help distribute the I/O load more evenly, reducing the risk of bottlenecks.

Configure additional SAN LIFs: Adding more SAN Logical Interfaces (LIFs) will ensure that the increased number of hosts can connect efficiently, improving load balancing and path management.

These actions help maintain optimal performance and prevent congestion in the SAN environment.

For more detailed guidance, refer to:

NetApp SAN Host Configuration Overview

NetApp Best Practices for SAN​ (NetApp)​​ (NetApp)

Implementing VLANs for NVMe/TCP configurations provides several benefits, two of which are increased resiliency and increased security:

Increased Resiliency: VLANs help segment the network traffic, reducing the risk of a single point of failure. By isolating NVMe/TCP traffic into specific VLANs, network issues can be contained within a VLAN, preventing them from affecting other parts of the network. This isolation ensures that disruptions are minimized and network resiliency is enhanced.

Increased Security: VLANs provide an added layer of security by segregating traffic. This segregation ensures that NVMe/TCP traffic is isolated from other types of traffic, reducing the risk of unauthorized access or data breaches. VLANs help in enforcing stricter access controls and monitoring, thereby increasing the overall security of the network.

For more information on the benefits of VLANs in NVMe/TCP configurations, you can refer to NetApp's technical resources:

Implementing and Configuring Modern SANs with NVMe-oF​ (NetApp)​.

SAN Configuration Best Practices​ (NetApp Community)​.