VLSR Planned Migration Stalls at 8%
search cancel

VLSR Planned Migration Stalls at 8%

book

Article ID: 437462

calendar_today

Updated On:

Products

VMware Live Recovery

Issue/Introduction

  • A planned migration for a protection group appears to stall at 8% completion for an extended period.
  • Replication of specific virtual machines is performingslow (e.g., taking over 30 minutes for a small final synchronization).
  • The recovery plan progress remains at 8% while waiting for the replication state to move from syncing to success.
  • No explicit error message is displayed in the Live Site Recovery interface, but the process does not progress.

Environment

  • Live Site Recovery (All Verions)
  • Replicated VMs utilizing vSphere Replication
  • VMware vSphere ESXi

Cause

This issue is caused by slow replication of a VM on the source ESXi host.

When an ESXi host detects high resource contention or prioritizes guest OS stability, it may throttle the replication bandwidth.  If the synchronization time still falls within the configured Recovery Point Objective (RPO) limits, the replication engine continues the transfer at the lower speed rather than failing, which causes the VLSR recovery plan to wait at the 8% synchronization step.

in /var/log/hostd.log on source ESXI host
grep -i "ReplicationScheduler" /var/log/hostd.log

Look for entries similar to: ReplicationScheduler: starting replica for group... Estimated maximum duration: 18907 seconds. Estimated average bandwidth: 0.28 MB/s.

Resolution

Allow Planned Migration to continue:

  • Do not cancel the recovery plan.
  • Allow the sync of the VM to complete. Progress can be monitored from the Replications "Incoming" or "Outgoing" tab

If low bandwidth utilization is found to be causing the slow sync progress:

  • Ensure port 31031, 32032 and 443 are not being throttled by physical firewalls or WAN optimizers
  • Ensure deep packet inspection is turned off on Firewall

If a single VM is being impacted and has a high estimated bandwidth calculation and a low actual bandwith utilization, perform a compute only vMotion of the VM to a new ESXi host in the cluster. 

 

Additional Information

Virtual machine replication is slow using vSphere Replication
Protecting a virtual machine using SRM and vSphere Replication fails with error: "Virtual machine is in an invalid state"

Powered by Wolken Software