Jenkins: Accessed denied. How to revert? 

You are probably getting this error because you enabled the security but don't have any user with permissions. To solve this problem, first edit config.xml and set useSecurity to false.

The config.xml file is under $JENKINS_HOME location. The default home for an Ubuntu installation would be under "/var/lib/jenkins" .

<?xml version='1.1' encoding='UTF-8'?> <hudson> <disabledAdministrativeMonitors/> <version>2.277.1</version> <numExecutors>2</numExecutors> <mode>NORMAL</mode> <useSecurity>false</useSecurity> <disableRememberMe>false</disableRememberMe>

If you want to use local authentication (a local db of users) Managed by Jenkins, rather than an external db (i.e., LDAP). Follow the steps below taken from Jenkins Documentation. Give the anonymous user the read access.

1. Go to the Configure Global Security screen (http://server/jenkins/configureSecurity/) and choose "enable security". An alternate URL to try is http://server:8080/configureSecurity.
2. Select "Jenkins's own user database" as the security realm
3. Place a check mark next to "Allow users to sign up"
4. Select "Matrix-based security" as the authorization
5. Give anonymous user the read access
6. In the text box below the table, type in your user name (you'd be creating this later) and click "add"
7. Give yourself a full access by checking the entire row for your user name
8. Scroll all the way to the bottom, click "save"

Thanks. Please share.