DUT: chromeos4-row10-jetstream-host6
Failed Build: https://uberchromegw.corp.google.com/i/chromeos/builders/whirlwind-paladin/builds/5990

Not exactly sure what failed...

2016/10/09 17:36:22.306 INFO |      auto_updater:0457| Waiting for update...status: UPDATE_STATUS_DOWNLOADING at progress 0.807968
2016/10/09 17:36:32.308 DEBUG|    cros_build_lib:0565| RunCommand: ssh -p 22 '-oConnectionAttempts=4' '-oUserKnownHostsFile=/dev/null' '-oProtocol=2' '-oConnectTimeout=30' '-oServerAliveCountMax=3' '-oStrictHostKeyChecking=no' '-oServerAliveInterval=10' '-oNumberOfPasswordPrompts=0' '-oIdentitiesOnly=yes' -i /tmp/ssh-tmp3ZNxiJ/testing_rsa root@100.115.219.28 -- update_engine_client --status
2016/10/09 17:36:57.654 ERROR|      auto_updater:0479| Rootfs update failed.
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2016/10/09 17:38:15.910 DEBUG|       cros_update:0224| Error happens in CrOS auto-update: RootfsUpdateError('Failed to perform rootfs update: RunCommandError("cwd=None, extra env={\'LC_MESSAGES\': \'C\'}", <chromite.lib.cros_build_lib.CommandResult object at 0x7f50c1028dd0>, None)',)