Rebalance file servers manually in vSAN 7.0

Products

• VMware vSAN

Issue/Introduction

When the file service cluster members or network are changed, the file servers may be imbalanced within the cluster. For example, the workload distribution check in the infrastructure health of file service may report warnings in the below situations:

• A host exit maintenance mode
• A host boots up
• A new host joins the cluster
• Network partition is recovered
• Total cluster failure and recovered

The hosts with higher workloads will be marked as yellow warnings.

Environment

VMware vSAN 7.0.x

Resolution

The user can ignore the warnings if they don’t see much performance degradation or use the Remediate Imbalance button to balance the workload. Please note that when Remediate Imbalance is triggered, the SMB service may be disrupted and the rebalance may impact any host in this cluster, not just the hosts with warnings. During the rebalance, I/O is disrupted to SMB shares located in containers that are being moved. Workloads running on NFS shares are not disrupted. If applications running on SMB shares can tolerate a short I/O disruption (usually less than 5 minutes), you can proceed with the rebalance task. If applications cannot tolerate a short I/O disruption, scheduling a maintenance window for the rebalance is recommended.