DRS in enabled and fully automated state in vCenter for NSX Host upgrade automation

Products

• VMware NSX

Issue/Introduction

In an NSX environment with a 3-host cluster, the host upgrade process requires moving hosts into maintenance mode to update NSX components (VIBs).

When VMware Distributed Resource Scheduler (DRS) is enabled, the NSX Upgrade Coordinator can automate this lifecycle, ensuring minimal disruption to running virtual machines.

Environment

VMware NSX

Cause

The automation of this process is dependent the vSphere DRS settings. For the workflow to proceed without manual intervention, DRS must be configured to handle the evacuation of workloads dynamically.

If DRS is set to "Manual" or "Partially Automated," or if the cluster lacks sufficient resources to host VMs on the remaining nodes, the automated upgrade workflow will stall and will need to be done manually

Resolution

To ensure a fully automated upgrade, verify and implement the following configurations:

• Set DRS to Fully Automated: Confirm the DRS Automation Level is set to Fully Automated. This allows vSphere to vMotion all running VMs to other hosts in the cluster automatically when the NSX Upgrade Coordinator requests maintenance mode.
• Verify Host Capacity: Ensure the 3-host cluster has enough CPU and RAM overhead to support all workloads on only two hosts while the third is being processed.
• Select Maintenance Mode Upgrade: In the NSX upgrade settings, choose the Maintenance Mode option rather than "In-place."
• Standard Workflow: Once configured, the Coordinator will sequentially place each host into maintenance mode, allow DRS to evacuate VMs, perform the VIB updates, and automatically exit maintenance mode before proceeding to the next host

Additional Information

Reference KBs: 

DRS should be Enabled and Fully automated for the cluster

NSX-T upgrade pre-check warning "DRS should be Enabled and Fully automated for the cluster containing host"

Upgrade Hosts