SAN Original Storage Architecture (OSA) Rolling Cache Tier Upgrade Procedure

Products

• VMware vSAN

Issue/Introduction

Introduction:

• This article provides guidance on performing rolling cache tier upgrades in a vSAN Original Storage Architecture (OSA) cluster.
• It addresses the supportability of mixed cache tier capacities during transitional periods and provides the necessary steps to ensure data accessibility.

Environment

VMware vSAN (OSA) (All supported versions).

Cause

Consultative

Resolution

Heterogeneous hardware configurations in the cache tier are fully supported during transitional rolling upgrade phases in a vSAN OSA cluster.

Follow the steps below to perform the upgrade safely:

1. Identify a host to upgrade within the vSAN OSA cluster.
2. Enter the host into Maintenance Mode. Ensure the selected data migration option ("Ensure Accessibility" or "Full Data Migration") is chosen based on FTT policies and available capacity.
3. Delete the existing disk group on the host Remove Disk Groups or Devices from vSAN
4. Remove the old cache drive and install the new 1.6 TB cache drive.
5. Create a new disk group on the host utilizing the new cache drive. Create a Disk Group or Storage Pool in vSAN Cluster
6. Exit Maintenance Mode and allow the cluster to resync.
7. Monitor resync activity for SSD congestion.
8. Repeat the process for subsequent hosts. Performance asymmetry may occur during the mixed state but will normalize once all nodes are upgraded.