Symptoms

After Reconfiguring K2 the cluster name and both individual servers are seen in the K2 Workspace management console where it previously showed only the cluster name.

 

Diagnoses

This can happen mainly because the workspace does a UDP broadcast on the K2 server discovery port (default is 49599 for server installs and 49600 for farm installs). The reconfigure might have used the wrong port.
 

Resolution 

To resolve this edit the K2HostServer.exe.config file which has the DiscoveryServiceListenPort set to the incorrect value.
It was set to 49599 and it should have been 49600.
Once updated only the cluster was visible in Workspace.
Also update the Management.xml file which alsomay have the incorrect port specified.