Confluence is installed at /opt/atlassian/confluence in CentOS environment, and the home directory is usally installed at /var/atlassian/application-data/confluence that is known as home directory. To reset confluence, what you should do is simply ereasing home directory. If your server accidentally does not work but the daily backup data is available, you can simple recover it by erasing the home directory.

If you installed your confluence server in default directory, you can simply reset your confluence by erasing the home directory like below:

# Stop confluence 
sudo service confluence stop

# Remove home directory to reset
sudo rm -rf /var/atlassian/application-data/confluence

# Start confluence
sudo service confluence start