I've got a jenkins CI installed from a debian package (1.424.6 version, Debian/Ubuntu distribution, running on ubuntu 12.04). I read on the web that jenkins provides an automatic upgrade button, just like in . But I don't have such thing on my jenkins. I tried to find answers on google and in jenkins config, but failed. Maybe it's impossible for debian/ubuntu installed package?
It's a permissions problem, If you trust in your Jenkins security configuration just run:
$ chown -R jenkins /usr/share/jenkins
Then restart jenkins and the upgrade button should be shown, and you can upgrade to last version, otherwise you have to use debian package system whose Jenkins version is not the latest.