@Sami Ahmad
You can use below link to clean up Ambari
https://community.hortonworks.com/questions/1110/how-to-completely-remove-uninstall-ambari-and-hdp.h...
Host Clean-up support in Ambari
Ambari currently has support to perform host check during host registration and produce an report based on the check. This report can also be used to perform clean-up.
When hosts are registered, the Ambari UI report issues as follows:

/usr/lib/python2.6/site-packages/ambari_agent/HostCleanup.py script can be invoked to perform cleanup of individual hosts. "python /usr/lib/python2.6/site-packages/ambari_agent/HostCleanup.py" is an interactive call and asks if "users" should be deleted. This is because for many setup may not want to remove users. Use --help to see other options.
python /usr/lib/python2.7/site-packages/ambari_agent/HostCleanup.py
You have elected to remove all users as well. If it is not intended then use option --skip "users". Do you want to continue [y/n] (n)
A newer version of the clean-up script is available on the trunk at HostCleanup.py that support a silent option (-s). This is specifically useful when cleaning up across multiple hosts, say using pdsh.
python /usr/lib/python2.7/site-packages/ambari_agent/HostCleanup.py --help
Usage: HostCleanup.py [options]
Options:
-h, --help show this help message and exit
-v, --verbose output verbosity.
-f FILE, --file=FILE host check result file to read.
-o FILE, --out=FILE log file to store results.
-k SKIP, --skip=SKIP (packages|users|directories|repositories|processes|alternatives). Use , as separator.
-s, --silent Silently accepts default prompt values
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