Cloudera Manager Health Test Issue Warning and Solution !

Cloudera Manager perform Multiple health test at regular Interval to Check Health of all Hadoop & Related Services.If any Health Test Failes it Show status of that service as Red.To Make All Services Like NameNode,DataNode,NodeManger,ResourceManager,Zookeeper etc its better aproach to fix all issue which are raised by health test.

• How to Open Cloudera manager in Window Laptop or desktop browser?

   For Non Secure access Cloudera Manager URL is available on Port  7180

       http://<<ClouderaManagerServer IP>>:7180/cmf/home

   For Secure TLS enabled,Cloudera Manager URL is available on Port  7183

       https://<<ClouderaManagerServer IP>>:7183/cmf/home

• How to Check Cloudera Manager Health Test  

         Login to Cloudera manager and goto All Health Issues Tab

1)Clock Offset

Description:The host's NTP service could not be located or did not respond to a request for the clock offset.
Solution:
                  -
                 -Identify NTP Server IP or Get details of NTP Server IP for your hadoop Cluster
                 -Login as root user
                 -On your Hadoop Cluster Nodes Edit-> /etc/ntp.conf
                 -Add entry-> "server <NTP Server IP>"
                 -Run "Service ntpd restart ",Restart Cluster From Cloudera Manager
                Note: If Problem Still Persist .Reboot you Hadoop Nodes & Check Process.

2)DNS Resolution

Description:Bad health issue
The hostname and canonical name for this host are not consistent when checked from a Java process.
Change Hostname and Canonical Name Health Check for all hosts
Solution:
                  -Vi 
                 -On your Hadoop Cluster Nodes Edit-> /etc/sysconfig/network
                 -Replace HOSTNAME="<hostname>" to -> Replace HOSTNAME="<FQDN>" 
                 -Eg HOSTNAME=clouderanamenode to HOSTNAME=clouderanamenode.xyz.com

                  -Reboot you Hadoop Nodes & Check Process.

3)Data Directory Status

Bad : The DataNode has 1 volume failure(s). Critical threshold: any.

Test of whether the DataNode has volume failures