@Jay SenSharma: Thanks for the quick response.
Also I am attaching the agent logs after restarting the ambari-server with iptables turned off: agentlog01.txt
if you are trying on HDP Sandbox, so I have mentioned try to reload on VMs...
As per the agent log ==>
Connection failed to http://xxx.yyy.ZZZ:8042/ws/v1/node/info
INFO 2017-05-09 10:09:21,700 logger.py:67 - Pid file /var/run/ambari-metrics-monitor/ambari-metrics-monitor.pid is empty or does not exist ERROR 2017-05-09 10:09:21,700 script_alert.py:112 - [Alert][ams_metrics_monitor_process] Failed with result CRITICAL: ['Ambari Monitor is NOT running on xxx.yyy.ZZZ'] ERROR 2017-05-09 10:09:21,701 script_alert.py:112 - [Alert][yarn_nodemanager_health] Failed with result CRITICAL: ['Connection failed to http://xxx.yyy.ZZZ:8042/ws/v1/node/info (Traceback (most recent call last):\n File "/var/lib/ambari-agent/cache/common-services/YARN/184.108.40.206.0/package/alerts/alert_nodemanager_health.py", line 165, in execute\n url_response = urllib2.urlopen(query, timeout=connection_timeout)\n File "/usr/lib64/python2.6/urllib2.py", line 126, in urlopen\n return _opener.open(url, data, timeout)\n File "/usr/lib64/python2.6/urllib2.py", line 391, in open\n response = self._open(req, data)\n File "/usr/lib64/python2.6/urllib2.py", line 409, in _open\n \'_open\', req)\n File "/usr/lib64/python2.6
below settings are initial setup, hope you already set it.
provide below output..it will help to narrow down the issue
-cat /etc/selinux/config|grep "SELINUX"
-service iptables status
-ntpd service enabled and running ? /etc/rc.d/init.d/ntpd status