This is the most effective and manageable approach. QoS policy groups allow for granular, set-and-forget control. Setting a minimum throughput for the critical database guarantees its performance, while capping the VMware workload prevents it from consuming resources needed by the database. This is superior to manual commands (error-prone), relying on automatic balancing (not guaranteed), or a single SVM-wide policy (lacks granularity).

Deduplication works on shared physical blocks. When nearly identical VMs are created, they share many blocks. However, if these shared blocks are referenced by an existing snapshot, they are accounted for as part of the snapshot’s space. A high snapshot reserve can make it appear that deduplication savings are low because the shared space is attributed to snapshots. Compression occurs after deduplication, cache pinning doesn’t affect background dedupe, and fpolicy typically doesn’t block deduplication.

This is the most direct and logical first step. `vserver nfs connected-clients show` confirms the client’s connection to the specific SVM and shows its mounted exports. Following up with `vserver nfs stats show -instance ` provides detailed, per-client NFS operation statistics (like latency, errors, ops/sec), which is crucial for diagnosing a performance issue isolated to a single client. Option A uses a generic statistics object, option C checks basic network connectivity (already confirmed healthy), and option D uses node-shell commands which are less targeted and not the recommended first-line diagnostic.

A steadily increasing lag with a stable network suggests the transfer pipeline on the destination is blocked or slow. `snapmirror show-destination-progress` is the key command. It shows the detailed status of transfers per-volume. Look for volumes stuck ‘Transferring’ (indicating a slow transfer) or ‘Queued’ (indicating they are waiting for resources, often because the max concurrent transfer limit for the node or cluster is reached). This identifies the bottleneck. Source-side changes (A, B) would cause a step-change in lag, not a steady increase. Destination-side efficiency (D) has minimal impact on transfer speed.

MetroCluster IP (or FC) with SyncMirror provides synchronous replication (RPO=0). The key component for meeting the ‘automatic failover… with minimal disruption’ is Automatic Unplanned Switchover (AUO). When enabled, AUO monitors the health of the partner site and can automatically initiate a switchover in case of a complete site failure, providing the lowest possible RTO without manual intervention. AsyncMirror (D) does not provide RPO=0. Manual switchover (B) increases RTO. A stretched cluster (C) is for high availability within a site, not for disaster recovery across sites.

In ONTAP, the concept of ‘thick provisioning’ is implemented via the space guarantee. `-space-guarantee volume` ensures that the entire logical size of the volume is pre-allocated (reserved) from the containing aggregate at creation time. This guarantees space and can influence performance by reducing fragmentation overhead. Fractional reserve (A) is a related but older concept primarily for LUNs within a volume. FlexGroup (C) uses thin provisioning by default. Snapshot policy (D) is unrelated to space guarantee for the active file system.

For a host to log in to a LUN, it must discover the target portal (the data LIF). If the data LIFs are not placed in the same broadcast domain/subnet as the host’s initiator ports, the host cannot establish a session, even if it can see the LUN via discovery protocols (which often use the cluster management LIF). This is a very common configuration oversight. OSType (A) affects alignment, not connectivity. ALUA settings (C) affect pathing, not initial login. LUN mapping indexes (D) above 255 are supported in modern ONTAP/Windows environments.

The final step in a SnapMirror-based migration/DR cutover is to ‘break’ the relationship on the destination volume. This action severs the replication link and changes the destination volume’s state from a read-only mirror to a read-write, independent volume. This is mandatory before clients can write to it. Creating a final snapshot (B) is done *before* the last update. DNS updates (C) are part of the client cutover process *after* the volume is read/write. Changing source exports to read-only (D) is a precaution but not the definitive step that enables writes on the destination.

High disk busy percentage directly indicates that the physical disks are heavily utilized, often the root cause of latency. If many disks in one aggregate are busy, that aggregate is a performance bottleneck. A key next step is to check if the aggregate’s SSD (performance tier) is being used efficiently. The `performance-tier-inactive-user-data` field shows how much cold data is sitting on expensive performance disks. If this value is high, moving that cold data to a capacity tier (FabricPool) could alleviate the disk load. High disk busy points to storage, not network (A) or CPU (D) initially. Failing disks (B) would likely show errors, not just high busy %.

This is the most effective and manageable approach. QoS policy groups allow for granular, set-and-forget control. Setting a minimum throughput for the critical database guarantees its performance, while capping the VMware workload prevents it from consuming resources needed by the database. This is superior to manual commands (error-prone), relying on automatic balancing (not guaranteed), or a single SVM-wide policy (lacks granularity).0