iscsi session cleanup now configurable, filters iscsi partitions (#4219)

Added property to agent.properties that enables or disables the iscsi session clean up feature. #4210
Added a condition to prevent disk partitions from being cleaned up. #4216

Author: skattoju4

agent/conf/agent.properties

@@ -218,3 +218,8 @@ hypervisor.type=kvm
 # timer.
 # For all actions refer to the libvirt documentation.
 # Recommended values are: none, reset and poweroff.
+#
+iscsi.session.cleanup.enabled=false
+# Automatically clean up iscsi sessions not attached to any VM.
+# Should be enabled for users using managed storage for example solidfire.
+# Should be disabled for users with unmanaged iscsi connections on their hosts

plugins/hypervisors/kvm/src/main/java/com/cloud/hypervisor/kvm/resource/LibvirtComputingResource.java

@@ -61,6 +61,7 @@
 import org.apache.commons.collections.MapUtils;
 import org.apache.commons.io.FileUtils;
 import org.apache.commons.lang.ArrayUtils;
+import org.apache.commons.lang.BooleanUtils;
 import org.apache.commons.lang.math.NumberUtils;
 import org.apache.log4j.Logger;
 import org.joda.time.Duration;
@@ -1088,9 +1089,15 @@ public boolean configure(final String name, final Map<String, Object> params) th
         storageProcessor.configure(name, params);
         storageHandler = new StorageSubsystemCommandHandlerBase(storageProcessor);
 
-        IscsiStorageCleanupMonitor isciCleanupMonitor = new IscsiStorageCleanupMonitor();
-        final Thread cleanupMonitor = new Thread(isciCleanupMonitor);
-        cleanupMonitor.start();
+        Boolean _iscsiCleanUpEnabled = Boolean.parseBoolean((String)params.get("iscsi.session.cleanup.enabled"));
+
+        if (BooleanUtils.isTrue(_iscsiCleanUpEnabled)) {
+            IscsiStorageCleanupMonitor isciCleanupMonitor = new IscsiStorageCleanupMonitor();
+            final Thread cleanupMonitor = new Thread(isciCleanupMonitor);
+            cleanupMonitor.start();
+        } else {
+            s_logger.info("iscsi session clean up is disabled");
+        }
 
         return true;
     }

plugins/hypervisors/kvm/src/main/java/com/cloud/hypervisor/kvm/storage/IscsiStorageCleanupMonitor.java

@@ -38,6 +38,7 @@ public class IscsiStorageCleanupMonitor implements Runnable{
     private static final String ISCSI_PATH_PREFIX = "/dev/disk/by-path";
     private static final String KEYWORD_ISCSI = "iscsi";
     private static final String KEYWORD_IQN = "iqn";
+    private static final String REGEX_PART = "\\S+part\\d+$";
 
     private IscsiAdmStorageAdaptor iscsiStorageAdaptor;
 
@@ -114,7 +115,7 @@ private void updateDiskStatusMapWithInactiveIscsiSessions(Connect conn){
 
                     //check the volume map. If an entry exists change the status to True
                     for (final LibvirtVMDef.DiskDef disk : disks) {
-                        if (diskStatusMap.containsKey(disk.getDiskPath())) {
+                        if (diskStatusMap.containsKey(disk.getDiskPath())&&!disk.getDiskPath().matches(REGEX_PART)) {
                             diskStatusMap.put(disk.getDiskPath(), true);
                             s_logger.debug("active disk found by cleanup thread" + disk.getDiskPath());
                         }