HDDS-1426. Minor logging improvements for MiniOzoneChaosCluster

Closes #730

hadoop-ozone/integration-test/src/test/bin/start-chaos.sh

@@ -15,7 +15,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-date=`date +"%m-%d-%y-%T"`
+date=`date +"%Y-%m-%d--%H-%M-%S-%Z"`
 fileformat=".MiniOzoneChaosCluster.log"
 heapformat=".dump"
 current="/tmp/"

hadoop-ozone/integration-test/src/test/java/org/apache/hadoop/ozone/MiniOzoneChaosCluster.java

@@ -87,11 +87,15 @@ public class MiniOzoneChaosCluster extends MiniOzoneClusterImpl {
   }
 
   private void failNodes() {
-    for (int i = 0; i < getNumberOfNodesToFail(); i++) {
+    final int numNodesToFail = getNumberOfNodesToFail();
+    LOG.info("Will restart {} nodes to simulate failure", numNodesToFail);
+    for (int i = 0; i < numNodesToFail; i++) {
       boolean failureMode = isFastRestart();
       int failedNodeIndex = getNodeToFail();
       try {
+        LOG.info("Restarting DataNodeIndex {}", failedNodeIndex);
         restartHddsDatanode(failedNodeIndex, failureMode);
+        LOG.info("Completed restarting DataNodeIndex {}", failedNodeIndex);
       } catch (Exception e) {
 
       }
@@ -118,7 +122,8 @@ public class MiniOzoneChaosCluster extends MiniOzoneClusterImpl {
   }
 
   void startChaos(long initialDelay, long period, TimeUnit timeUnit) {
-    LOG.info("Starting Chaos with failure period:{} unit:{}", period, timeUnit);
+    LOG.info("Starting Chaos with failure period:{} unit:{} numDataNodes:{}",
+        period, timeUnit, numDatanodes);
     scheduledFuture = executorService.scheduleAtFixedRate(this::fail,
         initialDelay, period, timeUnit);
   }