The slave https://integration.wikimedia.org/ci/computer/integration-slave-precise-1011/ went offline, it apparently rejects the SSH key:
[08/24/15 14:34:34] [SSH] Opening SSH connection to 10.68.17.70:22. ERROR: Server rejected the 1 private key(s) for jenkins-deploy (credentialId:ae711ff4-813e-4462-9a27-21bdbd4fdcb9/method:publickey) [08/24/15 14:34:34] [SSH] Authentication failed. hudson.AbortException: Authentication failed. at hudson.plugins.sshslaves.SSHLauncher.openConnection(SSHLauncher.java:1178) at hudson.plugins.sshslaves.SSHLauncher$2.call(SSHLauncher.java:701) at hudson.plugins.sshslaves.SSHLauncher$2.call(SSHLauncher.java:696) at java.util.concurrent.FutureTask.run(FutureTask.java:262) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615) at java.lang.Thread.run(Thread.java:745) [08/24/15 14:34:34] Launch failed - cleaning up connection [08/24/15 14:34:34] [SSH] Connection closed.