See https://uberchromegw.corp.google.com/i/chromeos/builders/falco-chrome-pfq/builds/5270.

Log information:
Triggered task: falco-chrome-pfq/R58-9237.0.0-rc2-sanity
chromeos-server22-238: 340d4ced6e564010 3
  Autotest instance: cautotest
  01-31-2017 [04:24:10] Submitted create_suite_job rpc
  Error Message: DevServerException: All devservers are currently down: set(['http://100.115.245.198:8082', 'http://100.115.245.197:8082', 'http://100.115.245.200:8082']). dut hostname: chromeos2-row3-rack4-host1
  Traceback (most recent call last):
    File "/usr/local/autotest/frontend/afe/json_rpc/serviceHandler.py", line 118, in dispatchRequest
      results['result'] = self.invokeServiceEndpoint(meth, args)
    File "/usr/local/autotest/frontend/afe/json_rpc/serviceHandler.py", line 158, in invokeServiceEndpoint
      return meth(*args)
    File "/usr/local/autotest/frontend/afe/rpc_handler.py", line 270, in new_fn
      return f(*args, **keyword_args)
    File "/usr/local/autotest/frontend/afe/rpc_utils.py", line 1353, in replacement
      return func(**kwargs)
    File "/usr/local/autotest/frontend/afe/site_rpc_interface.py", line 253, in create_suite_job
      test_source_build, hostname=sample_dut)
    File "/usr/local/autotest/frontend/afe/site_rpc_interface.py", line 128, in _stage_build_artifacts
      ds = dev_server.resolve(build, hostname=hostname)
    File "/usr/local/autotest/client/common_lib/cros/dev_server.py", line 2350, in resolve
      return ImageServer.resolve(build, hostname)
    File "/usr/local/autotest/client/common_lib/cros/dev_server.py", line 721, in resolve
      raise DevServerException(error_msg)
  DevServerException: All devservers are currently down: set(['http://100.115.245.198:8082', 'http://100.115.245.197:8082', 'http://100.115.245.200:8082']). dut hostname: chromeos2-row3-rack4-host1