Unable to update plugins after the Jenkins 1.514 upgrade.

There is no proxy set up in Manage Plugins advanced tab.

I get the below error for plugins update. I could access the link http://updates.jenkins-ci.org/update-center.json?uctest from a browser on the same machine without any issue.

java.io.FileNotFoundException: http://updates.jenkins-ci.org/update-center.json?uctest at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1434) at hudson.model.UpdateCenter$UpdateCenterConfiguration.testConnection(UpdateCenter.java:862) at hudson.model.UpdateCenter$UpdateCenterConfiguration.checkUpdateCenter(UpdateCenter.java:711) at hudson.model.UpdateCenter$ConnectionCheckJob.run(UpdateCenter.java:1032) at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:441) at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303) at java.util.concurrent.FutureTask.run(FutureTask.java:138) at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) at java.lang.Thread.run(Thread.java:680)