That seems strange. Can you explain and be more precise. Ambari server reset just deletes all the cluster data in Ambari server database and puts default schema. It does not touch any namenode data/binaries.
As it's a single node cluster you don't have much to lose just go ahead and recreate a new cluster. !
A backup copy of your Ambari database is good insurance to keep your Ambari server running. Anytime you make changes to Ambari you should create a backup of the Ambari database before you make the changes. You will want to do this if you need to restore your cluster to the original state
Thank you for your response.
As i said unexpectedly it is showing above attached page .i.e., it is a displaying a page that when we open ambari UI on 8080 port for the 1st time immediately after setting up the ambari-server .
we didn't took the ambari database backup previously .will it help if we do it now.
We usually take backups of a consistent database and I am afraid yours isn't. It would be a good idea to backup the DB after the successful setup of the cluster.
As reiterated the ambari-reset deleted the cluster information in the database. So should maybe create a cron entry to do a daily or on-demand backup of your Ambari database especially after heavy configuration changes