2078223 - "Cannot get list of all agents" during Managed System Configuration and other EM related errors - Solution Manager 7.1 and 7.2

When doing the managed system configuration, on step "8 - Configure Automatically" -> "Introscope Host Adapter", the following Error happens:

com.sap.sup.admin.wily.jdbc.ConfigurationException: Cannot get list of all agents
at com.sap.sup.admin.wily.jdbc.ServerNameMappingStrategy.getAgentsByLogicalHost(ServerNameMappingStrategy.java:77)

The following errors can also be found in the Enterprise Manager related logs:

Time out occurred when calling method 'run' on object [com.sap.smd.server.util.concurrent.FutureResult$1@279df09c] after 30000 ms.

com.sap.smd.introscope.em.IntroscopeException: All configured Enterprise Managers are offline - check configuration.

com.sap.smd.introscope.em.IntroscopeException: connection attempt already in progress

Solution Manager 7.1

Solution Manager 7.2

com.sap.sup.admin.wily.jdbc.ConfigurationException: Cannot get list of all agents
at com.sap.sup.admin.wily.jdbc.ServerNameMappingStrategy.getAgentsByLogicalHost(ServerNameMappingStrategy.java:77)  Time out occurred when calling method 'run' on object [com.sap.smd.server.util.concurrent.FutureResult$1@279df09c] after 30000 ms. com.sap.smd.introscope.em.IntroscopeException: All configured Enterprise Managers are offline - check configuration. com.sap.smd.introscope.em.IntroscopeException: connection attempt already in progress Enterprise Manager , EM Diagnostics , Managed System Configuration ,  step 8  , Configure Automatically , Introscope Host Adapter , KBA , SV-SMG-DIA-WLY-EMS , Enterprise Manager Setup , Problem