vCenter task flooded with "Cause: A general system error occurred: Host is in maintenance mode" generated from vSphere replication due to scanned host in maintenance mode.

Products

• VMware vSphere ESXi
• VMware vCenter Server
• VMware Site Recovery Manager 8.x

Issue/Introduction

Symptoms:

• vCenter UI flooded with task generated by vSphere replication while it scans host which are placed in maintenance mode.

Environment

vCenter 8.x

vSphere ESX 7.x,8.x

vSphere replication 8.x,9.x

Cause

vSphere Replication automatically discovers and registers all hosts within the vCenter Server's inventory. 

When the hms service discovers the ESX host in maintenance mode it will log the message in the vCenter.

When the host is placed in maintenance mode it closes connection over port 443 on the ESXi for hbrsrvuw service causing the replication to report the issue with these hosts.

Resolution

NOTE: Please take a snapshot of the vSphere replication appliance before using the below steps.

If you want to exclude hosts or a cluster of hosts under a given cluster or datacenter from registration in vSphere Replication, you can tag them with the com.vmware.vr.disallowedHost tag.

Please follow the below image to add the above tag to the host which is in maintenance mode.

Restart the hms service from the VR ssh session using the below command 
systemctl stop hms
systemctl start hms.

The above steps will help to stop the task checking for the reporting hosts.

Additional Information

The same hosts will be visible with their details in the vSphere replication apliance as per the below KB.

The host details will appear along with the hostname/IP in the vSphere replication task pane as below 

The above messages also are cleared once the above resolution is followed.