A username and password was setup for all the jobs in jenkins. However that person left our ogranization. Now I have to use a different username and password for subversion (SVN) in all the jobs. I used credentials plugin to configure it centrally. But after I did that it says "none" in the place of SVN credentials in all the jobs. I have to manually select the new credential from drop down. Is there a way to bulk edit all the jobs to use the new username and password for SVN?
Jenkins stores job configuration in a file called config.xml (one for each job) under the [JENKINS_HOME]/jobs/[JOBNAME]/ directory.
So you can edit your xml's to change it with new config. You can use sed + regex to make the change easyest with terminal.
Here is the Jenkins documentation with this folder estructure info.