I have installed Jenkins on an ec2 Ubuntu 18.04 LTS server based on these instructions: https://linuxize.com/post/how-to-install-jenkins-on-ubuntu-18-04/
When I go to Jenkins in my browser I get the "Unlock Jenkins" page:
Unlock Jenkins To ensure Jenkins is securely set up by the administrator, a password has been written to the log (not sure where to find it?) and this file on the server:
/var/lib/jenkins/secrets/initialAdminPassword
Please copy the password from either location and paste it below.
ERROR: The password entered is incorrect, please check the file for the correct password
But the folder /var/lib/jenkins/secrets/ does not contain the initialAdminPassword file.
I tried temporarily turning off security based on How to reset Jenkins security settings from the command line? but the "useSecurity" tag in config.xml gets reset to "true" every time I restart Jenkins.
I also tried this, but was still not able to find the password file Unlock Jenkins - how to