AMBARI-2500. Host confirmation fails if ambari-agent is already run. (Myroslav via mahadev)

git-svn-id: https://svn.apache.org/repos/asf/incubator/ambari/trunk@1497104 13f79535-47bb-0310-9956-ffa450edef68

ambari-server/src/main/python/setupAgent.py

@@ -77,7 +77,7 @@ def configureAgent(server_hostname):
 
 def runAgent(passPhrase, expected_hostname):
   os.environ[AMBARI_PASSPHRASE_VAR] = passPhrase
-  agent_retcode = subprocess.call("/usr/sbin/ambari-agent start --expected-hostname=" + expected_hostname, shell=True)
+  agent_retcode = subprocess.call("/usr/sbin/ambari-agent restart --expected-hostname=" + expected_hostname, shell=True)
   try:
 
     ret = execOsCommand(["tail", "-20", "/var/log/ambari-agent/ambari-agent.log"])