Article number
000003317
Affected Versions
6.5 Update 4 Patch 1
6.5 Update 4
6.5 Update 3 Patch 1
6.5 Update 3
6.5 Update 2
6.5 Update 1 Patch 1
6.5 Update 1
6.5
Source Hypervisor
All
Target Hypervisor
All

Problem with Slow Replication/Syncs Halting After Upgrade to Zerto 6.5

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Summary

After upgrading to Zerto version 6.5, an administrator may notice that overall replication and syncs are slow/stuck.

Root Cause

Bandwidth regulator is not allowing available bandwidth to distribute across VRAs correctly so some VRA replication/syncs are stalled.

Symptoms

VPGs will get stuck in a bitmap or delta sync.

VPGs that are not syncing actively may show higher than normal RPO figures.

Bandwidth Regulator logs on the Protected Site will show some VRAs have a "BwLim" of a very small number (in bytes per second):

VraBwLimit,server=<SERVER_GUID> host=<HOST_MOREF>,VraBwLim=206
VraBwLimit,server=<SERVER_GUID> host=<HOST_MOREF>,VraBwLim=3
VraBwLimit,server=<SERVER_GUID> host=<HOST_MOREF>,VraBwLim=500
VraBwLimit,server=<SERVER_GUID> host=<HOST_MOREF>,VraBwLim=1
VraBwLimit,server=<SERVER_GUID> host=<HOST_MOREF>,VraBwLim=1

Solution

To workaround this issue, disable Bandwidth Regulator entirely from the Site Settings menu in the Zerto GUI on the Protected Site.

This issue was permanently resolved in Zerto version 7.0.