diff --git a/core/src/com/cloud/resource/ResourceListener.java b/core/src/com/cloud/resource/ResourceListener.java
new file mode 100755
index 00000000000..a94e3940629
--- /dev/null
+++ b/core/src/com/cloud/resource/ResourceListener.java
@@ -0,0 +1,92 @@
+package com.cloud.resource;
+
+import java.net.URI;
+import java.util.List;
+import java.util.Map;
+
+import com.cloud.host.HostVO;
+
+public interface ResourceListener {
+    static final Integer EVENT_DISCOVER_BEFORE = 0x1;
+    static final Integer EVENT_DISCOVER_AFTER = 0x1 << 1;
+    static final Integer EVENT_DELETE_HOST_BEFORE = 0x1 << 2;
+    static final Integer EVENT_DELETE_HOST_AFTER = 0x1 << 3;
+    static final Integer EVENT_CANCEL_MAINTENANCE_BEFORE = 0x1 << 4;
+    static final Integer EVENT_CANCEL_MAINTENANCE_AFTER = 0x1 << 5;
+    static final Integer EVENT_PREPARE_MAINTENANCE_BEFORE = 0x1 << 6;
+    static final Integer EVENT_PREPARE_MAINTENANCE_AFTER = 0x1 << 7;
+    static final Integer EVENT_ALL = (EVENT_DISCOVER_BEFORE | EVENT_DISCOVER_AFTER | EVENT_DELETE_HOST_BEFORE | EVENT_DELETE_HOST_AFTER
+            | EVENT_CANCEL_MAINTENANCE_BEFORE | EVENT_CANCEL_MAINTENANCE_AFTER | EVENT_PREPARE_MAINTENANCE_BEFORE | EVENT_PREPARE_MAINTENANCE_AFTER);
+
+    String getName();
+    
+    /**
+     * 
+     * @param dcid
+     * @param podId
+     * @param clusterId
+     * @param uri
+     * @param username
+     * @param password
+     * @param hostTags
+     * 
+     * Called before Discover.find()
+     */
+    void processDiscoverEventBefore(Long dcid, Long podId, Long clusterId, URI uri, String username, String password, List<String> hostTags);
+
+    /**
+     * 
+     * @param resources
+     * 
+     * Called after Discover.find()
+     */
+    void processDiscoverEventAfter(Map<? extends ServerResource, Map<String, String>> resources);
+
+    /**
+     * 
+     * @param host
+     * 
+     * Called before host delete
+     */
+    void processDeleteHostEventBefore(HostVO host);
+
+    /**
+     * 
+     * @param host
+     * 
+     * Called after host delete. NOTE param host includes stale data which has been removed from database
+     */
+    void processDeletHostEventAfter(HostVO host);
+
+    /**
+     * 
+     * @param hostId
+     * 
+     * Called before AgentManager.cancelMaintenance
+     */
+    void processCancelMaintenaceEventBefore(Long hostId);
+
+    /**
+     * 
+     * @param hostId
+     * 
+     * Called after AgentManager.cancelMaintenance
+     */
+    void processCancelMaintenaceEventAfter(Long hostId);
+
+    /**
+     * 
+     * @param hostId
+     * 
+     * Called before AgentManager.main
+     */
+    void processPrepareMaintenaceEventBefore(Long hostId);
+
+    /**
+     * 
+     * @param hostId
+     * 
+     * Called after AgentManager.main
+     */
+    void processPrepareMaintenaceEventAfter(Long hostId);
+}