@irfangk1  Edge nodes are the interface between the Hadoop cluster and the outside network. They’re also often used as staging areas for data being transferred into the Hadoop cluster. Installing the edge node is as easy as adding a node to the cluster. The only difference is that on the edge-node you will only deploy client software ONLY e.g SQOOP, PIG, HDFS, YARN, HBase, SPARK, ZK HIVE or HUE etc to enable you to for example to run HDFS commands on the edge-node. To enable communication between the outside network and the Hadoop cluster, edge nodes need to be multi-homed into the private subnet of the Hadoop cluster as well as into the corporate network. A multi-homed computer is one that has dedicated connections to multiple networks. This is a practical illustration of why edge nodes are perfectly suited for interaction with the world outside the Hadoop cluster. Keeping your Hadoop cluster in its own private subnet is an excellent practice, so these edge nodes serve as a controlled window inside the cluster If you're using Knox for perimeter security, then all clients' software should reside on a dedicated Knox gateway machine to which end users can submit their requests.It's good practice to divide the cluster into master nodes, worker nodes, edge node(s), and management node. Services such as Namenode, Zookeeper, Yarn Resource Manager, Secondary Namenode usually run on the master node machines. Worker nodes aka Datanode should be further divided into two categories those running HDFS and Yarn and those running Storm and Kafka and other components A minimum best practice is to have 3-5 master and >5 data nodes. HTH ... View more

@Jena  Great patience never give up 😁😂. I think your problem is now resolved I suspect incompatibility problem with IE 11 I need to check the documentation later today. Please take some time to accept my reponse as valid answer  so other members can use 8t to resolve the same issue. Happy hadooping ... View more

@ThanhP  There you go a happy member 😁😂 Please get some time and accept my solution so other members can use it to solution the same problem. Happy hadooping !!! ... View more

@ThanhP    The log says the opposite "Started ServerConnector@7692d9cc{HTTP/1.1,[http/1.1]}{0.0.0.0:9995}" I think you should be hitting the wrong port or IP.  How have you set up your network?  Bridged/NAT, can you share the output of  $ ifconfig If you are launching Zeppelin through Ambari Login to Ambari (operations console) as user  amy_ds/amy_ds  username/password combination.  http://sandbox-hdp.hortonworks.com:9995 Please share your feedback ... View more

@irfangk1    That means you didn't install MySQL. Can I ask you one question? What documentation are you using as a reference?The basic steps are described when you are preparing the environment. To me it seems you launched the deployment using the embedded database Postgresql but now you want to switch to MySQL. To do that you need to install mysql and pre-create the ambari database before launching the Ambari server setup, that explains why you are getting all those errors. I can send you a procedure in 9 hours ... View more

@irfangk1  Can you share the screenshot of your Ambari Hive config  because when I see "jdbc:mysql://host.com/metastore" "hive"   that means you dont have  not The default  TCP port  for PostgreSQL is usually 5432 see in the postgresql.conf ... View more

@irfangk1  If you switched to Mysql why do you have these entries in your ambari.properties   server.jdbc.database=postgres server.jdbc.database_name=ambari server.jdbc.postgres.schema=ambari   Can you share the output of  # cat /etc/ambari-server/conf/ambari.properties | grep mysql Why is that in the log again I see  "jdbc:mysql://host.com/metastore" "hive"  where is the PORT  number?   ... View more