Unable to update/install Jenkins plugins

Question

Hi I'm not able to Update/Install any plugins in Jenkins getting this error below.

Branch API  Failure -

java.io.FileNotFoundException: http://updates.jenkins-ci.org/download/plugins/branch-api/2.5.6/branch-api.hpi
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1890)
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1492)
    at sun.net.www.protocol.http.HttpURLConnection.getHeaderField(HttpURLConnection.java:3000)
    at java.net.URLConnection.getHeaderFieldLong(URLConnection.java:629)
    at java.net.URLConnection.getContentLengthLong(URLConnection.java:501)
    at java.net.URLConnection.getContentLength(URLConnection.java:485)
    at hudson.model.UpdateCenter$UpdateCenterConfiguration.download(UpdateCenter.java:1126)
Caused: java.io.FileNotFoundException: http://updates.jenkins-ci.org/download/plugins/branch- 
api/2.5.6/branch-api.hpi
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at 
sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
    at 
sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
    at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
    at sun.net.www.protocol.http.HttpURLConnection$10.run(HttpURLConnection.java:1944)
    at sun.net.www.protocol.http.HttpURLConnection$10.run(HttpURLConnection.java:1939)
    at java.security.AccessController.doPrivileged(Native Method)
    at 
sun.net.www.protocol.http.HttpURLConnection.getChainedException(HttpURLConnection.java:1938)
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1508)
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1492)
    at hudson.model.UpdateCenter$UpdateCenterConfiguration.download(UpdateCenter.java:1139)
Caused: java.io.IOException: Failed to load http://updates.jenkins-ci.org/download/plugins/branch-api/2.5.6/branch-api.hpi to /var/lib/jenkins/plugins/branch-api.jpi.tmp

Also when I try Check Now in manage plugin -> advance getting this error:

A problem occurred while processing the request. Please check our bug tracker to see if a similar problem has already been reported. If it is already reported, please vote and put a comment on it to let us gauge the impact of the problem. If you think this is a new issue, please file a new issue. When you file an issue, make sure to add the entire stack trace, along with the version of Jenkins and relevant plugins. The users list might be also useful in understanding what has happened.
Stack trace
sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
    at sun.security.provider.certpath.SunCertPathBuilder.build(SunCertPathBuilder.java:141)
    at sun.security.provider.certpath.SunCertPathBuilder.engineBuild(SunCertPathBuilder.java:126)
    at java.security.cert.CertPathBuilder.build(CertPathBuilder.java:280)
    at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:392)
Caused: sun.security.validator.ValidatorException: PKIX path building failed
    at sun.security.validator.PKIXValidator.doBuild(PKIXValidator.java:397)
    at sun.security.validator.PKIXValidator.engineValidate(PKIXValidator.java:302)
    at sun.security.validator.Validator.validate(Validator.java:260)
    at sun.security.ssl.X509TrustManagerImpl.validate(X509TrustManagerImpl.java:324)
    at sun.security.ssl.X509TrustManagerImpl.checkTrusted(X509TrustManagerImpl.java:229)
    at sun.security.ssl.X509TrustManagerImpl.checkServerTrusted(X509TrustManagerImpl.java:124)
    at sun.security.ssl.ClientHandshaker.serverCertificate(ClientHandshaker.java:1596)
Caused: javax.net.ssl.SSLHandshakeException
    at sun.security.ssl.Alerts.getSSLException(Alerts.java:192)
    at sun.security.ssl.SSLSocketImpl.fatal(SSLSocketImpl.java:1964)    

Thanks

Answer 1

Your update site is wrong; https://updates.jenkins.io/ . Fix under /pluginManager/advanced .

Also, 2.5.6 is still several years and releases obsolete, as is most likely your Jenkins instance itself.