I can't give a perfect solution but I can give you a solution that might work if you do it good. There is no direct plugin to do this. So that's why I am giving you my solution. But this a little complex to be built.
First of all Setup a Jenkins server with good and updated configuration. Now make a zip file of ~/.jenkins
folder. So now please replace the ~/.jenkins
folder of all the other jenkins server instances with this configured jenkins instance zip file. This is just for the initial set up.
Use this plugin to watch the file system changes of job config's. Create a job for this. And in the build step, create a zip file having all the changed config files and info file having where to place where file i.e. changed_configs.json ( [file_name_in_zip_file, location_to_be_pasted] ).
After this has been done, Please save this zip file in the nfs share. Please use the same plugin task for checking whether is there any change in the nfs share location. If any change, that means that job config has been updated. So now using that changed_configs.json file do the replacement of configs and now all are in sync with the other.
By the way each server will be having two jobs to do this. one will check for job config changes and make a zip file. Other will be checking for zip files change in the nfs share location.
Configure these two jobs also while making instance zip file. Now please use this to change the configuration in running instance. Manage Jenkins
=> Reload Configuration from Disk
use this option to reload config from the xml files again. Make it in the build step itself after replacing the changed configs. It will be quick and don't need the restart of your jenkins. Hope this helps. This is complex but can be useful in your case as there are no inbetween applications or connectivity between servers.
Some urls you can look into are:
How to move Jenkins from one PC to another?
https://staxmanade.com/2015/01/how-to-migrate-a-jenkins-job-to-new-jenkins-server/
https://wiki.jenkins.io/display/JENKINS/Job+Import+Plugin