Error: No connection to VR Server for virtual machine on host in cluster : Unknown'. while configuring replication for VM

Products

• VMware Live Recovery

Issue/Introduction

When reconfiguring replication job in vSphere replication UI getting following error:

Error: No connection to VR Server for virtual machine on host in cluster : Unknown'.
Synchronization monitoring has stopped. Please verify replication traffic connectivity between the source host and the target vSphere Replication Server. Synchronization monitoring will resume when connectivity issues are resolved.

Environment

vSphere replication appliance 9.x

Cause

The causes of this problem are usually numerous and include configuration issues with the VR appliance and ESXi host, errors or modifications, and environmental issues with the network, firewall, etc.

 
vmkernel.log (In Source ESXi host) shows below details,

2025-03-24T04:33:23.862Z Wa(180) vmkwarning: cpu9:9488281)WARNING: Hbr: 571: Con
nection failed to 127.0.0.1 (groupID=GID-xxxxxxxxx-xxxx-4ced-a314-xxxxxxxxxxxx):Broken Pipe

hbr-agent.log shows below details:
2025-06-05T19:56:06.146Z In(166) hbr-agent-bin[2101685]: [0x000000c263c77700] error: [Proxy [Group: GID-xxxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxx] -> [[<IPv4 or IPv6 address>%1]:32032]] Failed to connect to [<IPv4 or IPv6 address>%1]:32032. Error: Connection timed out
2025-06-05T19:56:06.146Z In(166) hbr-agent-bin[2101685]: [0x000000c263c77700] error: [Proxy [Group: GID-xxxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxx] -> [[<IPv4 or IPv6 address>%1]:32032]] Failed to connect to server [<IPv4 or IPv6 address>%1]:32032 using broker info: Connection timed out
2025-06-05T19:56:06.147Z In(166) hbr-agent-bin[2101685]: [0x000000c263d79700] error: [Proxy [Group: GID-xxxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxx] -> [[<IPv4 or IPv6 address>%1]:32032]] Exhausted all server endpoints reported by broker.
2025-06-05T19:56:21.144Z In(166) hbr-agent-bin[2101685]: [0x000000c263d79700] info: [Proxy [Group: GID-xxxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxx] -> [[2620:137:4011:26ad:0:4:ee01:202]:32032]] Setting up secure tunnel to brokered server [<IPv4 or IPv6 address>%1]:32032 (1 of 1)
2025-06-05T19:56:21.144Z In(166) hbr-agent-bin[2101685]: [0x000000c263d79700] info: [Proxy [Group: GID-xxxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxx] -> [[<IPv4 or IPv6 address>%1]:32032]] Connecting to [<IPv4 or IPv6 address>%1]:32032 without specific vmk
2025-06-05T19:56:42.186Z In(166) hbr-agent-bin[2101685]: [0x000000c263d79700] error: [Http] Unexpected HTTP status code: 500
2025-06-05T19:57:36.148Z In(166) hbr-agent-bin[2101685]: [0x000000c263c77700] error: [Proxy [Group: GID-xxxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxx] -> [[<IPv4 or IPv6 address>%1]:32032]] Failed to connect to [<IPv4 or IPv6 address>%1]:32032. Error: Connection timed out
2025-06-05T19:57:36.148Z In(166) hbr-agent-bin[2101685]: [0x000000c263c77700] error: [Proxy [Group: GID-xxxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxx] -> [[<IPv4 or IPv6 address>%1]:32032]] Failed to connect to server [<IPv4 or IPv6 address>%1]:32032 using broker info: Connection timed out
2025-06-05T19:57:36.148Z In(166) hbr-agent-bin[2101685]: [0x000000c263d79700] error: [Proxy [Group: GID-xxxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxx] -> [[<IPv4 or IPv6 address>%1]:32032]] Exhausted all server endpoints reported by broker.

Resolution

Reboot host reported in the 

2025-06-05T19:57:36.148Z In(166) hbr-agent-bin[2101685]: [0x000000c263c77700] error: [Proxy [Group: GID-xxxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxx] -> [[<IPv4 or IPv6 address>%1]:32032]] Failed to connect to [<IPv4 or IPv6 address>%1]:32032. Error: Connection timed out

to re-establish the port 32032 communication.