Site Recovery plugin fails to download in the vCenter server

Products

VMware Live Recovery

Issue/Introduction

Symptoms:

VMware Site Recovery plug-in fails to deploy in vCenter
Re-registering the appliance with the vCenter server may resolve the issue for some time

Download plug-in errors:

Error downloading plug-in. Make sure that the URL is reachable and the registered thumbprint is correct. #########: Name or service not known

Cannot complete the operation. See the event log for details. Error downloading plug-in. URL is unreachable. status code: 503, reason phrase: Service Unavailable

Environment

VMware Live Site Recovery Manager 8.x
VMware Live Site Recovery Manager 9.x
VMware vSphere Replication 8.x
VMware vSphere Replication 9.x
VMware vCenter Server 7.x
VMware vCenter Server 8.x

Resolution

Plug-in log locations:

vCenter - /var/log/vmware/vsphere-ui/logs/vsphere_client_virgo.log
SRM/VRMS - /var/log/vmware/dr-client-plugin/drplugin.log

Before proceeding with the below action plan, try and open the vCenter in an incognito tab or a different browser to check if the plug-in still shows failed. Sometimes, due to the browser cache the plug-in will keep on showing failed and does not show the site recovery plug-in.
Opening the vCenter in an incognito tab should show the correct plug-in deployed.
In case we still see the plug-in status as failed, continue following the below action plan.
Check if the required ports are open between the vCenter server and the DR appliance

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NOTE: Take powered OFF snapshots of vCenter. Ignore the PSC, if you don't have it.

1. Record the ESXi host on which vCenter and PSC is homed
2. Set DRS to manual mode for the clusters in which these hosts reside.
3. Login to vCenter & PSC VAMI. Shutdown the vCenters first followed by the PSCs.
4. Once all nodes are shutdown, snapshot vCenter & PSC from the host client.
5. Power ON the PSCs first followed by the vCenter

Note : For vCenter server 6.x and below replace vsphere-ui with vsphere-client in the below commands.

root@VCSA [ ~ ]# service-control --stop vsphere-ui (Any vCenter users logged in will be logged off)
Operation not cancellable. Please wait for it to finish...
Performing stop operation on service vsphere-ui...
Successfully stopped service vsphere-ui

root@VCSA [ ~ ]# cd /usr/lib/vmware-vsphere-ui/server/work/
root@VCSA [ /usr/lib/vmware-vsphere-ui/server/work ]# ls
root@VCSA [ /usr/lib/vmware-vsphere-ui/server/work ]# rm -rf *

root@VCSA [ ~ ]# cd /storage/vsphere-ui/SerenityDB/serenity

root@VCSA [ /storage/vsphere-ui/SerenityDB/serenity ]# ls
root@VCSA [ /storage/vsphere-ui/SerenityDB/serenity ]# rm -rf *

root@VCSA [ ~ ]# cd /etc/vmware/vsphere-ui/vc-packages/vsphere-client-serenity/
root@VCSA [ /etc/vmware/vsphere-ui/vc-packages/vsphere-client-serenity ]# ls
com.dell.emc.nw-19.6.0.94  com.vmware.lcm.client-7.0.3.500  com.vmware.vrops.install-7.0.203.10000  com.vmware.vsphere.client.h5vsan-7.0.203.10000 com.vmware.vxrail-9.1.0.0
root@VCSA [ /etc/vmware/vsphere-ui/vc-packages/vsphere-client-serenity ]# rm -rf *

root@VCSA [ ~ ]# cd /etc/vmware/vsphere-ui/cmCatalog
root@VCSA [ /etc/vmware/vsphere-ui/cmCatalog ]# ls
root@VCSA [ /etc/vmware/vsphere-ui/cmCatalog ]# rm -rf *

NOTE: Only remove older version or unwanted plug-ins from this location.

root@VCSA [ ~ ]# cd /etc/vmware/vsphere-ui/cm-service-packages/com.vmware.cis.vsphereclient.plugin
root@VCSA [ /etc/vmware/vsphere-ui/cm-service-packages/com.vmware.cis.vsphereclient.plugin ]# ls
com.vmware.h4.vsphere.client-0.4.3.0  com.vmware.vrUi-8.5.0.18710000  com.vmware.vrUi-8.6.0.20554592  com.vmware.vum.client-7.0.3.19478898

root@VCSA [ /etc/vmware/vsphere-ui/cm-service-packages/com.vmware.cis.vsphereclient.plugin ]# rm -rf com.vmware.vrUi-8.5.0.18710000
root@VCSA [ /etc/vmware/vsphere-ui/cm-service-packages/com.vmware.cis.vsphereclient.plugin ]# ls
com.vmware.h4.vsphere.client-0.4.3.0  com.vmware.vrUi-8.6.0.20554592  com.vmware.vum.client-7.0.3.19478898

root@VCSA [ ~ ]# service-control --start vsphere-ui
Operation not cancellable. Please wait for it to finish...
Performing start operation on service vsphere-ui...
Successfully started service vsphere-ui

If the issue is resolved, remove all snapshots at once if vCenter/PSC is in ELM (Enhanced Linked Mode).

Additional Information

Note: If the issue is still not resolved then remove the SRM plugin from vCenter server and reconfigure the SRM appliance to deploy the SRM plugin on the vCenter server.

Impact/Risks:

1. Stopping the vSphere client UI service will log out users logged into vCenter

2. Restarting all vCenter services when backups are running will stall all running backup jobs.

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