@Michael Bronson Few checks will be good to perform: 1. To verify is ambari is showing false Running AMS services? Please check the AMS collector hosts if the AMS collector is actually running and listening to the correct address/port: # netstat -tnlpa | grep 6188 # hostname -f 2. Please verify if the AMS process PID are matching with the PIDs that are listed int he following files. Some times not matching PIDs causes false info in the UI $ ps -ef | grep ^ams | grep ApplicationHistoryServer $ cat /var/run/ambari-metrics-collector/ambari-metrics-collector.pid $ ps -ef | grep ^ams | grep HMaster $ cat /var/run/ambari-metrics-collector/hbase-ams-master.pid . 3. Can you try restarting the AMS collector Service once to see if you notice any error int he AMS collector logs? . ... View more

@Michael Bronson Yes, NTPD is one of the major requirement to make all the cluster nodes in sync. THis is specially very important when we run Kerberized cluster because the tgt has a direct link with the time. (which is ususlly known as "Clock Skew Error") This is one of thew prerequisite of Cluster preparation: https://docs.hortonworks.com/HDPDocuments/Ambari-2.6.1.5/bk_ambari-installation-ppc/content/enable_ntp_on_the_cluster_and_on_the_browser_host.html The clocks of all the nodes in your cluster and the machine that runs the browser through which you access the Ambari Web interface must be able to synchronize with each other. . ... View more

@Mudassar Hussain Can you please try this: 1. Instead of copying the "authorized_key" file using SCP try the following command from ambari server host. Please make sure that you are using the correct FQDN of node4 in the following command. From Ambari Server Host # ssh-copy-id -i ~/.ssh/id_rsa.pub root@node4 . 2. Now on the host (node4) check if the FQDN is set correctly? On Node4 (check if it has ambari.repo file and it's contents are fine) # hostname -f # cat /etc/hosts # cat /etc/yum.repos.d/ambari.repo # yum install ambari-agent -y . Now try from ambari UI again. If it still does not work then try the following approach Then check if the following command shows the correct ambari Hostname in the "ambari-agent.ini" file? Example: # grep -A 1 '\[server\]' /etc/ambari-agent/conf/ambari-agent.ini [server] hostname=ambari1.example.com . If not then edit it then try again from ambari. ... View more

@Anurag Mishra The HDFS Service is a combination of various components like NameNoides, DataNodes, ZKFC, JournalNodes ..etc So the Service Up time really does not make much sense because in a Service 90% components might be UP but some of them (10%) might be down ... So i will suggest you to check the "Service Component" UP time instead of finding the "Service" up time. The easiest option to capture the "Service Component" uptime will be to see the "uptime" field in the following command for the component: For example finding DataNode Uptime: # ps -ef | grep `cat /var/run/hadoop/hdfs/hadoop-hdfs-datanode.pid` | awk 'NR==1{print $5 " - " $7}' Mar02 - 03:43:47 . Similarly you can run the following commands to find NameNode, JournalNode Uptime ...etc # ps -ef | grep `cat /var/run/hadoop/hdfs/hadoop-hdfs-journalnode.pid` | awk 'NR==1{print $5 " - " $7}' # ps -ef | grep `cat /var/run/hadoop/hdfs/hadoop-hdfs-namenode.pid` | awk 'NR==1{print $5 " - " $7}' . The output of Column 5 and column 7 shows the Uptime (date & time) Example: # ps -ef | grep `cat /var/run/hadoop/hdfs/hadoop-hdfs-namenode.pid` root 519 31846 0 23:23 pts/0 00:00:00 grep --color=auto 17262 hdfs 17262 1 0 Mar02 ? 07:55:29 /usr/jdk64/jdk1.8.0_112/bin/java -Dproc_namenode -Xmx1024m -Dhdp.version=2.6.1.0-129 -Djava.net.preferIPv4Stack=true -Dhdp.version= -Djava.net.preferIPv4Stack=true -Dhdp.version= -Djava.net.preferIPv4Stack=true -Dhadoop.log.dir=/var/log/hadoop/hdfs.......... -Dhadoop.security.logger=INFO,RFAS org.apache.hadoop.hdfs.server.namenode.NameNode . ... View more