SystemVM: Set agent state to disconnected on Stopping the systemVM (#5010)

Fixes: #4972
This PR sets systevms' agent state to disconnected when it is stopped. Currently, when a systemVM (Console Proxy VM / Secondary storage VM) is stopped, the agent state still appears to be 'Up'

Author: Pearl1594

api/src/main/java/com/cloud/host/Status.java

@@ -131,6 +131,9 @@ public static String[] toStrings(Status... states) {
         s_fsm.addTransition(Status.Up, Event.PingTimeout, Status.Alert);
         s_fsm.addTransition(Status.Up, Event.AgentDisconnected, Status.Alert);
         s_fsm.addTransition(Status.Up, Event.ShutdownRequested, Status.Disconnected);
+        s_fsm.addTransition(Status.Disconnected, Event.ShutdownRequested, Status.Disconnected);
+        s_fsm.addTransition(Status.Down, Event.ShutdownRequested, Status.Disconnected);
+        s_fsm.addTransition(Status.Rebalancing, Event.ShutdownRequested, Status.Disconnected);
         s_fsm.addTransition(Status.Up, Event.HostDown, Status.Down);
         s_fsm.addTransition(Status.Up, Event.Ping, Status.Up);
         s_fsm.addTransition(Status.Up, Event.AgentConnected, Status.Connecting);

api/src/main/java/com/cloud/vm/VirtualMachine.java

@@ -20,6 +20,8 @@
 import java.util.Date;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
+import java.util.HashSet;
 
 import org.apache.cloudstack.acl.ControlledEntity;
 import org.apache.cloudstack.api.Displayable;
@@ -186,6 +188,7 @@ public static boolean isVmDestroyed(State oldState, Event e, State newState) {
         }
     }
 
+    static final Set<Type> systemVMs = new HashSet<>(Arrays.asList(VirtualMachine.Type.ConsoleProxy, VirtualMachine.Type.SecondaryStorageVm));
     static final String IsDynamicScalingEnabled = "enable.dynamic.scaling";
 
     public enum Event {

engine/orchestration/src/main/java/com/cloud/vm/VirtualMachineManagerImpl.java

@@ -40,6 +40,7 @@
 import javax.inject.Inject;
 import javax.naming.ConfigurationException;
 
+import com.cloud.api.ApiDBUtils;
 import org.apache.cloudstack.affinity.dao.AffinityGroupVMMapDao;
 import org.apache.cloudstack.api.ApiConstants;
 import org.apache.cloudstack.api.command.admin.vm.MigrateVMCmd;
@@ -1984,6 +1985,14 @@ private void advanceStop(final VMInstanceVO vm, final boolean cleanUpEvenIfUnabl
                     s_logger.warn("Unable to actually stop " + vm + " but continue with release because it's a force stop");
                     vmGuru.finalizeStop(profile, answer);
                 }
+            } else {
+                if (VirtualMachine.systemVMs.contains(vm.getType())) {
+                    HostVO systemVmHost = ApiDBUtils.findHostByTypeNameAndZoneId(vm.getDataCenterId(), vm.getHostName(),
+                            VirtualMachine.Type.SecondaryStorageVm.equals(vm.getType()) ? Host.Type.SecondaryStorageVM : Host.Type.ConsoleProxy);
+                    if (systemVmHost != null) {
+                        _agentMgr.agentStatusTransitTo(systemVmHost, Status.Event.ShutdownRequested, _nodeId);
+                    }
+                }
             }
         }
 

server/src/main/java/com/cloud/api/ApiResponseHelper.java

@@ -1450,7 +1450,7 @@ public SystemVmResponse createSystemVmResponse(VirtualMachine vm) {
                 }
             }
 
-            if (vm.getType() == Type.SecondaryStorageVm || vm.getType() == Type.ConsoleProxy) {
+            if (VirtualMachine.systemVMs.contains(vm.getType())) {
                 Host systemVmHost = ApiDBUtils.findHostByTypeNameAndZoneId(vm.getDataCenterId(), vm.getHostName(),
                         Type.SecondaryStorageVm.equals(vm.getType()) ? Host.Type.SecondaryStorageVM : Host.Type.ConsoleProxy);
                 if (systemVmHost != null) {