FATAL: Failed to fetch from ssh://<gitid>@<githost>/<gitrepo>.git
hudson.plugins.git.GitException: Failed to fetch from ssh://<gitid>@<githost>/<gitrepo>.git
   at hudson.plugins.git.GitSCM.fetchFrom(GitSCM.java:623)
   at hudson.plugins.git.GitSCM.retrieveChanges(GitSCM.java:855)
   at hudson.plugins.git.GitSCM.checkout(GitSCM.java:880)
   at hudson.model.AbstractProject.checkout(AbstractProject.java:1411)
   at hudson.model.AbstractBuild$AbstractBuildExecution.defaultCheckout(AbstractBuild.java:652)
   at jenkins.scm.SCMCheckoutStrategy.checkout(SCMCheckoutStrategy.java:88)
   at hudson.model.AbstractBuild$AbstractBuildExecution.run(AbstractBuild.java:561)
   at hudson.model.Run.execute(Run.java:1665)
   at hudson.matrix.MatrixRun.run(MatrixRun.java:146)
   at hudson.model.ResourceController.execute(ResourceController.java:88)
   at hudson.model.Executor.run(Executor.java:246)
Caused by: hudson.plugins.git.GitException: org.eclipse.jgit.api.errors.TransportException: ssh://<gitid>@<githost>/<gitrepo>.git: Failed to connect
   at org.jenkinsci.plugins.gitclient.JGitAPIImpl$2.execute(JGitAPIImpl.java:460)
   at org.jenkinsci.plugins.gitclient.RemoteGitImpl$CommandInvocationHandler$1.call(RemoteGitImpl.java:153)
   at org.jenkinsci.plugins.gitclient.RemoteGitImpl$CommandInvocationHandler$1.call(RemoteGitImpl.java:146)
   at hudson.remoting.UserRequest.perform(UserRequest.java:118)
   at hudson.remoting.UserRequest.perform(UserRequest.java:48)
   at hudson.remoting.Request$2.run(Request.java:328)
   at hudson.remoting.InterceptingExecutorService$1.call(InterceptingExecutorService.java:72)
   at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:345)
   at java.util.concurrent.FutureTask.run(FutureTask.java:177)
   at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1121)
   at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:614)
   at java.lang.Thread.run(Thread.java:769)
Caused by: org.eclipse.jgit.api.errors.TransportException: ssh://<gitid>@<githost>/<gitrepo>.git: Failed to connect
   at org.eclipse.jgit.api.FetchCommand.call(FetchCommand.java:139)
   at org.jenkinsci.plugins.gitclient.JGitAPIImpl$2.execute(JGitAPIImpl.java:458)
   ... 11 more
Caused by: org.eclipse.jgit.errors.TransportException: ssh://<gitid>@<githost>/<gitrepo>.git: Failed to connect
   at org.jenkinsci.plugins.gitclient.trilead.TrileadSessionFactory.getSession(TrileadSessionFactory.java:53)
   at org.eclipse.jgit.transport.SshTransport.getSession(SshTransport.java:121)
   at org.eclipse.jgit.transport.TransportGitSsh$SshFetchConnection.<init>(TransportGitSsh.java:248)
   at org.eclipse.jgit.transport.TransportGitSsh.openFetch(TransportGitSsh.java:147)
   at org.eclipse.jgit.transport.FetchProcess.executeImp(FetchProcess.java:136)
   at org.eclipse.jgit.transport.FetchProcess.execute(FetchProcess.java:122)
   at org.eclipse.jgit.transport.Transport.fetch(Transport.java:1111)
   at org.eclipse.jgit.api.FetchCommand.call(FetchCommand.java:130)
   ... 12 more
Caused by: java.io.InvalidClassException: com.cloudbees.jenkins.plugins.sshcredentials.SSHAuthenticator$1; local class incompatible: stream classdesc serialVersionUID = 4226456448964168241, local class serialVersionUID = 8217644684038495097
    at java.io.ObjectStreamClass.initNonProxy(ObjectStreamClass.java:604)
    at java.io.ObjectInputStream.readNonProxyDesc(ObjectInputStream.java:1620)
    at java.io.ObjectInputStream.readClassDesc(ObjectInputStream.java:1515)
    at java.io.ObjectInputStream.readOrdinaryObject(ObjectInputStream.java:1769)
    at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1348)
    at java.io.ObjectInputStream.readObject(ObjectInputStream.java:370)
    at hudson.remoting.UserRequest.deserialize(UserRequest.java:182)
    at hudson.remoting.UserRequest.perform(UserRequest.java:98)
    at hudson.remoting.UserRequest.perform(UserRequest.java:48)
    at hudson.remoting.Request$2.run(Request.java:328)
    at hudson.remoting.InterceptingExecutorService$1.call(InterceptingExecutorService.java:72)
    at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
    at java.util.concurrent.FutureTask.run(FutureTask.java:166)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at java.lang.Thread.run(Thread.java:722)