I'm trying to do cros flash my veyron_minnie through ethernet cable and I get the following error. At first I thought it might be some stale state in my chroot, but after clobbering chroot, repo sync I still get the same error. Even I checked out a new repo but still failed. I tried on branch M60 and it worked fine. Seems like some new CL's have messed this up.

~/trunk $ cros flash --debug 172.22.30.184 veyron_minnie_test_image_R57-9202.60.bin 
12:30:22: DEBUG: Cache dir lookup.
12:30:22: DEBUG: Configured cache_dir to '/mnt/host/source/.cache'
12:30:22: NOTICE: Preparing to update the remote device 172.22.30.184
12:30:22: INFO: RunCommand: ping -c 1 -w 20 172.22.30.184
12:30:22: INFO: Using image veyron_minnie_test_image_R57-9202.60.bin
12:30:22: INFO: Copying image to temporary directory /tmp/dev_server_wrapper_local_imagehmEpiU
12:30:26: INFO: Creating a symlink /mnt/host/source/devserver/static/local_imagepYl7OS/link -> /tmp/dev_server_wrapper_local_imagehmEpiU
12:30:26: DEBUG: Assuming local_imagepYl7OS/link/test is an xbuddy path.
12:30:26: INFO: Starting local devserver to generate/serve payloads...
12:30:26: DEBUG: RunCommand: sudo 'CROS_CACHEDIR=/mnt/host/source/.cache' -- start_devserver --pidfile /tmp/devserver_wrapperCra0my/devserver_wrappertYyO4o --logfile /tmp/devserver_wrapperCra0my/dev_server.log '--port=0' --critical_update '--portfile=/tmp/devserver_wrapperCra0my/dev_server.port' '--static_dir=/mnt/host/source/devserver/static' in /mnt/host/source
12:30:31: DEBUG: Retrieving http://127.0.0.1:37330/check_health
12:30:31: DEBUG: Retrieving http://172.22.112.223:37330/xbuddy/local_imagepYl7OS/link/test?for_update=true&return_dir=true
12:31:47: ERROR: Devserver responded with HTTP error (HTTP Error 500: Internal Server Error)
12:31:47: DEBUG: RunCommand: sudo 'CROS_CACHEDIR=/mnt/host/source/.cache' -- test -f /tmp/devserver_wrapperCra0my/dev_server.log
12:31:47: DEBUG: RunCommand: sudo 'CROS_CACHEDIR=/mnt/host/source/.cache' -- tail -n 50 /tmp/devserver_wrapperCra0my/dev_server.log
12:31:47: WARNING: --- Start output from /tmp/devserver_wrapperCra0my/dev_server.log ---[08/Aug/2017:12:30:27] ENGINE (wait_for_occupied_port) Waiting for actual port 37330.
[08/Aug/2017:12:30:27] ENGINE Serving on :::0
[08/Aug/2017:12:30:27] ENGINE Bus STARTED
::ffff:127.0.0.1 - - [08/Aug/2017:12:30:31] "GET /check_health HTTP/1.1" 200 371 "" "Python-urllib/2.7"
[08/Aug/2017:12:30:31] XBUDDY Cannot find /mnt/host/source/src/build/images; skip syncing image registry.
[08/Aug/2017:12:30:31] XBUDDY Path is local_imagepYl7OS/link/test, location suffix is -release
[08/Aug/2017:12:30:31] XBUDDY Get artifact 'test' with board local_imagepYl7OS and version link'. Locally? True
[08/Aug/2017:12:30:31] XBUDDY Returning path to payload: local_imagepYl7OS/link/chromiumos_test_image.bin
[08/Aug/2017:12:30:31] XBUDDY Downloading ['full_payload', 'stateful'] from gs://chromeos-image-archive/local_imagepYl7OS/link
[08/Aug/2017:12:30:31] UTIL Error happened while reading lsb-release file: cat: /etc/lsb-release: No such file or directory
[08/Aug/2017:12:30:31] GOOGLE_STORAGE_DOWNLOADER Downloading artifacts *_full_*->/mnt/host/source/devserver/static/local_imagepYl7OS/link stateful.tgz->/mnt/host/source/devserver/static/local_imagepYl7OS/link.
[08/Aug/2017:12:30:31] A_U_TEST_PAYLOAD No marker file, *_full_*->/mnt/host/source/devserver/static/local_imagepYl7OS/link is not staged.
[08/Aug/2017:12:30:32] XBUDDY Cannot find /mnt/host/source/src/build/images; skip syncing image registry.
[08/Aug/2017:12:30:32] XBUDDY Path is local_imagepYl7OS/link/test, location suffix is -release
[08/Aug/2017:12:30:32] XBUDDY Get artifact 'test' with board local_imagepYl7OS and version link'. Locally? True
[08/Aug/2017:12:30:32] XBUDDY Updating timestamp for local_imagepYl7OS/link
[08/Aug/2017:12:30:32] XBUDDY Returning path to payload: local_imagepYl7OS/link/chromiumos_test_image.bin
[08/Aug/2017:12:30:32] DEVSERVER Payload generation triggered by request
[08/Aug/2017:12:30:32] UPDATE Update label/file: local_imagepYl7OS/link/chromiumos_test_image.bin
[08/Aug/2017:12:30:32] UPDATE Generating update for src  image /mnt/host/source/devserver/static/local_imagepYl7OS/link/chromiumos_test_image.bin
[08/Aug/2017:12:30:39] UPDATE Caching in sub_dir "cache/d7465148a827cfc55a2902cf2e2b1ab0"
[08/Aug/2017:12:30:39] UPDATE Generating update for image /mnt/host/source/devserver/static/local_imagepYl7OS/link/chromiumos_test_image.bin
[08/Aug/2017:12:30:39] UPDATE Generating update image /mnt/host/source/devserver/static/cache/d7465148a827cfc55a2902cf2e2b1ab0/update.gz
[08/Aug/2017:12:30:39] UPDATE Running cros_generate_update_payload --image /mnt/host/source/devserver/static/local_imagepYl7OS/link/chromiumos_test_image.bin --out_metadata_hash_file /mnt/host/source/devserver/static/cache/d7465148a827cfc55a2902cf2e2b1ab0/metadata_hash --output /mnt/host/source/devserver/static/cache/d7465148a827cfc55a2902cf2e2b1ab0/update.gz
[08/Aug/2017:12:31:20] UPDATE Running cros_generate_stateful_update_payload --image /mnt/host/source/devserver/static/local_imagepYl7OS/link/chromiumos_test_image.bin --output_dir /mnt/host/source/devserver/static/cache/d7465148a827cfc55a2902cf2e2b1ab0
[08/Aug/2017:12:31:47] HTTP Traceback (most recent call last):
  File "/usr/lib64/python2.7/site-packages/cherrypy/_cprequest.py", line 656, in respond
    response.body = self.handler()
  File "/usr/lib64/python2.7/site-packages/cherrypy/lib/encoding.py", line 188, in __call__
    self.body = self.oldhandler(*args, **kwargs)
  File "/usr/lib64/python2.7/site-packages/cherrypy/_cpdispatch.py", line 34, in __call__
    return self.callable(*self.args, **self.kwargs)
  File "/usr/lib/devserver/devserver.py", line 1462, in xbuddy
    image_name=file_name)
  File "/usr/lib64/devserver/autoupdate.py", line 490, in GetUpdateForLabel
    rel_path = self.GenerateUpdateImageWithCache(static_image_path)
  File "/usr/lib64/devserver/autoupdate.py", line 423, in GenerateUpdateImageWithCache
    self.GenerateUpdateImage(image_path, cache_dir)
  File "/usr/lib64/devserver/autoupdate.py", line 389, in GenerateUpdateImage
    raise AutoupdateError('Failed to generate update in %s' % output_dir)
AutoupdateError: Failed to generate update in /mnt/host/source/devserver/static/cache/d7465148a827cfc55a2902cf2e2b1ab0

[08/Aug/2017:12:31:47] HTTP 
Request Headers:
  HOST: 172.22.112.223:37330
  CONNECTION: close
  Remote-Addr: ::ffff:172.22.112.223
  USER-AGENT: Python-urllib/2.7
  ACCEPT-ENCODING: identity
::ffff:172.22.112.223 - - [08/Aug/2017:12:31:47] "GET /xbuddy/local_imagepYl7OS/link/test?for_update=true&return_dir=true HTTP/1.1" 500 1890 "" "Python-urllib/2.7"
--- End output from /tmp/devserver_wrapperCra0my/dev_server.log ---
12:31:47: DEBUG: Stopping devserver instance with pid 1469
12:31:47: DEBUG: RunCommand: sudo 'CROS_CACHEDIR=/mnt/host/source/.cache' -- kill 1469
12:31:47: DEBUG: RunCommand: sudo 'CROS_CACHEDIR=/mnt/host/source/.cache' -- rm -rf -- /mnt/host/source/devserver/static/local_imagepYl7OS
12:31:47: DEBUG: RunCommand: sudo 'CROS_CACHEDIR=/mnt/host/source/.cache' -- rm -rf -- /tmp/dev_server_wrapper_local_imagehmEpiU
12:31:47: ERROR: Device update failed.
12:31:47: DEBUG: 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-tmpSjUOgb/testing_rsa root@172.22.30.184 -- cat /etc/lsb-release
12:31:48: ERROR: Error connecting to device 172.22.30.184
12:31:48: INFO: You can find the log files and/or payloads in /tmp/cros-flash8LFChv
12:31:48: DEBUG: RunCommand: sudo 'CROS_CACHEDIR=/mnt/host/source/.cache' -- rm -rf -- /tmp/devserver_wrapperCra0my
12:31:48: ERROR: cros flash failed before completing.
cros: Unhandled exception:
Traceback (most recent call last):
  File "/mnt/host/source/chromite/bin/cros", line 168, in <module>
    DoMain()
  File "/mnt/host/source/chromite/bin/cros", line 164, in DoMain
    commandline.ScriptWrapperMain(FindTarget)
  File "/mnt/host/source/chromite/lib/commandline.py", line 829, in ScriptWrapperMain
    ret = target(argv[1:])
  File "/mnt/host/source/chromite/scripts/cros.py", line 65, in main
    code = _RunSubCommand(subcommand)
  File "/mnt/host/source/chromite/scripts/cros.py", line 50, in _RunSubCommand
    return subcommand.Run()
  File "/mnt/host/source/chromite/cli/cros/cros_flash.py", line 150, in Run
    debug=self.options.debug)
  File "/mnt/host/source/chromite/cli/flash.py", line 555, in Flash
    updater.Run()
  File "/mnt/host/source/chromite/cli/flash.py", line 466, in Run
    if device_connected and device.lsb_release:
  File "/mnt/host/source/chromite/lib/remote_access.py", line 1004, in lsb_release
    content = self.CatFile(constants.LSB_RELEASE_PATH, max_size=None)
  File "/mnt/host/source/chromite/lib/remote_access.py", line 838, in CatFile
    error_code_ok=True, capture_output=True)
  File "/mnt/host/source/chromite/lib/remote_access.py", line 889, in BaseRunCommand
    return self.GetAgent().RemoteSh(cmd, **kwargs)
  File "/mnt/host/source/chromite/lib/remote_access.py", line 344, in RemoteSh
    raise SSHConnectionError(e.result.error)
chromite.lib.remote_access.SSHConnectionError: Warning: Identity file /tmp/ssh-tmpSjUOgb/testing_rsa not accessible: No such file or directory.
Warning: Permanently added '172.22.30.184' (RSA) to the list of known hosts.
Permission denied (publickey,keyboard-interactive).