I'm using latest Jenkins (v 1.590) LOL, but Jenkins official site say: 1.588. I'm 200% sure that I did see 1.589 and 1.590 few days back on Jenkins official download site(when I wanted to upgrade Jenkins to newer version).
This is what I see at the bottom of my Jenkins instance page.
Page generated: Nov 19, 2014 12:07:51 PMREST APIJenkins ver. 1.590
Now, the issue I'm facing is: Since I upgraded few of the plugins and Jenkins itself recently, some of the jobs are missing (I see this can happen during upgrades but upgrading to latest Jenkins should fix it and I'm two steps ahead of what Jenkins has on their official site, right):
I see valid .jpi files for respective plugins in plugins folder in JENKINS_HOME and there are some .pinned files as well. I have tried this a couple of times but the plugins are not visible once installed. Installation doesn't give any error during the whole operation.
Jenkins system log file (upon Jenkins restart) is attached (NOTE: Use slow download button to see/download this log file).
Download at SpeedyShare or [code]http://speedy.sh/x6vd8/Jenkins.System.Log[/code]
Issue was with the plugins permissions and expanded folders.
If you see under the plugins folder, you'll see .jpi or .hpi files (Jenkins jpi and Hudson hpi).
If I have awesomeplugin.jpi then there will be a folder called awesomeplugin.
Using Slav's hint, I ran bunch of checks and found out of 70+ plugins that I had installed, few of them somehow got "root" and "root" as their owner and group for their .jpi files and corresponding folder.
Now, The best solution one can try (the safest approach) is to chown -R yourvalidjenkinsuser:yourvalidgroup * and chmod -R 755 * as root. Before doing this, stop/shutdown jenkins.
I went even a step further, I first took backup of config files / whole jenkins JENKINS_HOME folder. Then I went to plugins folder and remove all .jpi corresponding folders using root account or as the owner of those folders (NOTE, I didn't delete the .jpi files). Then, I ran the above two commands (chown/chmod) and started Jenkins.
OUTCOME:
when I'm going to Jenkins > New item (to create a new job), Shenzi, all different types of jobs options are showing up (which included the Maven2/3 type job which I found got missing and few others like "Multi-configuration project" and Multijob Project job type.. all were missing and now they are showing up.
OK, I also checked one of the old job, went to its job's configuration and Shenzi!! I now see all the features there i.e. (Promoted Job plugin feature "Promtoe builds when.." check box. This feature which I configured sometime back, got missing but now it's showing up again.
Few of the Maven jobs that I created in past with Maven Release Plugin and Release Plugin POC work had bunch of steps in it. I found there was nothing in the Build step (after this whole mess), but after the above solution, I now see everything is back. I can see the configurations and build steps populated as they were set.
I hope this can help someone facing similar issue.
Still, I don't know why my Jenkins version is 1.590 (which Jenkins updated recently in automatic fashion) and Jenkins site today says, their latest Jenkins artifact is version 1.588 (seems like a mystery).