When you upgrade your VDP from 5.8.x to/ot 6.0.x to/or 6.1.x you will need to uninstall the old backup agent, re download the new agent from the 6.1.x Configuration Tab and install it. However, this installation will fail with the below error:
This is because the client was not deactivated once the agent was uninstalled. Until you deactivate the client associated with the old plugin you will not be able to install the new one.
On the machine where you are installing the client, if you browse to C:\Program Files\avp\var you will have a log file called avagent.log and if you notice the error here, you will see:
2017-05-19 14:09:37 avagent Error <6210>: Unable to register '/clients/VDPApps\sqlvm' with MCS at 192.x.x.x:28001
2017-05-19 14:09:37 avagent Error <6163>: Registration error: MCS returned error code 110, '* 110 * Re-registration of account /clients/VDPApps/sqlvm.happycow.local is not permitted'
2017-05-19 14:09:37 avagent Error <7531>: Unable to register /clients/VDPApps/sqlvm with Administrator 192.x.x.x:28001
So, to deactivate this client, from the SSH of the VDP run the below command:
# mccli client edit --activated=false --name=/clients/VDPApps/<client-fqdn>
Then retry the install of the agent and it should complete successfully.
Hope this helps.
