@Deepak SANAGAPALLI
The following kind of message indicates some filesystem issue:
Unable to access /var/log/ambari-server directory. Confirm the directory is created and is writable by Ambari Server user account 'root'
.
So please check if you have the mentioned directory created and you are able to create some dummy files inside that dir.
# echo "Test" > /var/log/ambari-server/test.log
# mkdir -p /var/log/ambari-server/one
Check if somehow the "/var/log" filesystem has become read-only by any chance? May be rebooting the host will help in such cases.
Also please check if the file "ambari.properties" is showing correct username there:
# grep 'ambari-server.user' /etc/ambari-server/conf/ambari.properties
ambari-server.user=root
.
