Which NetApp SnapMirror method allows for transparent failover between two AFF clusters with applications using iSCSI LUNs?

SnapMirror Business Continuity (SM-BC) is the specific NetApp technology designed to provide continuous availability and transparent application failover (TAF) for SAN workloads, including iSCSI LUNs. It combines synchronous replication with a mediator service to orchestrate an automatic or manual failover between two AFF clusters. This process is transparent to the application servers, which continue to access their LUNs without interruption or requiring host-side changes, thus ensuring business continuity.

B. SnapVault: This is a disk-to-disk backup and archival solution for long-term retention and disaster recovery, not for providing transparent, real-time application failover.

C. SVM-DR: This is a disaster recovery feature that replicates an entire Storage Virtual Machine (SVM). Failover is a disruptive process that requires manual intervention or scripting to activate the destination SVM.

D. SMS: This refers to SnapMirror Synchronous mode, which provides zero RPO data replication. While it is a core component of SM-BC, it is not the complete solution that delivers transparent application failover.

1. NetApp Technical Report TR-4742

"SnapMirror Business Continuity: Technical Overview."

Section: Introduction

Page 4.

Quote: "NetApp SnapMirror Business Continuity (SM-BC) is a feature in NetApp ONTAP 9.8 and later data management software that provides business continuity for business-critical applications. SM-BC enables transparent application failover (TAF) over a SAN." This document explicitly links SM-BC to transparent failover for SAN applications.

2. NetApp ONTAP 9 Documentation

"Data protection overview."

Section: "SnapMirror Synchronous replication" and "SnapMirror Business Continuity".

Content: The documentation distinguishes SM-S as the replication mode providing an RPO of zero

while defining SM-BC as the complete solution built upon SM-S that adds the transparent application failover capability for SAN environments.

3. NetApp ONTAP 9 Documentation

"SVM disaster recovery overview."

Section: "What SVM disaster recovery is".

Content: This section describes SVM-DR as a disaster recovery solution where

in the event of a disaster

you must "break the SnapMirror relationship and bring the destination SVM online

" which is a manual

disruptive process

not a transparent one.