mvn gcloud:run starts, but app is not responsive

[bfg]

After i run gcloud:run, docker starts, admin server works, but app doesn't respond after logging in.

Beginning interaction for module default...                                                                                                                                                                                                                                    
Success.
Temporary staging for module default directory left in /tmp/1432908080183-0
[INFO] Running gcloud app run...
[INFO] Getting project name: play7app from gcloud settings.
[INFO] Running python -S /home/bfg/google-cloud-sdk/bin/dev_appserver.py -A play7app /home/bfg/git/appengine-java-vm-hello/target/hello-1.0-SNAPSHOT
[INFO] INFO     2015-05-29 14:01:21,222 application_configuration.py:399] No version specified. Generated version id: 20150529t140121
[INFO] INFO     2015-05-29 14:01:21,222 devappserver2.py:745] Skipping SDK update check.
[INFO] INFO     2015-05-29 14:01:21,249 api_server.py:190] Starting API server at: http://localhost:49013
[INFO] INFO     2015-05-29 14:01:21,278 containers.py:259] Building docker image play7app.default.20150529t140121 from /home/bfg/git/appengine-java-vm-hello/target/hello-1.0-SNAPSHOT/Dockerfile:
[INFO] INFO     2015-05-29 14:01:21,278 dispatcher.py:192] Starting module "default" running at: http://localhost:8080
[INFO] INFO     2015-05-29 14:01:21,278 containers.py:261] --------------------  DOCKER BUILD  --------------------
[INFO] INFO     2015-05-29 14:01:21,279 admin_server.py:118] Starting admin server at: http://localhost:8000
[INFO] INFO     2015-05-29 14:01:21,538 containers.py:280] Step 0 : FROM gcr.io/google_appengine/java-compat
[INFO] INFO     2015-05-29 14:01:21,565 containers.py:280] ---> e146f963ba55
[INFO] INFO     2015-05-29 14:01:21,566 containers.py:280] Step 1 : ADD . /app
[INFO] INFO     2015-05-29 14:01:21,714 containers.py:280] ---> ea6080b21c4a
[INFO] INFO     2015-05-29 14:01:21,737 containers.py:280] Removing intermediate container 0a3f4dbb345d
[INFO] INFO     2015-05-29 14:01:21,737 containers.py:280] Successfully built ea6080b21c4a
[INFO] INFO     2015-05-29 14:01:21,741 containers.py:292] --------------------------------------------------------
[INFO] INFO     2015-05-29 14:01:21,741 containers.py:304] Image play7app.default.20150529t140121 built, id = ea6080b21c4a
[INFO] INFO     2015-05-29 14:01:21,742 containers.py:534] Creating container...
[INFO] INFO     2015-05-29 14:01:21,824 containers.py:560] Container 0cf80f82acfe5171e7ae274a47d03bc9ac5515aac4b85d70ebf3c1443c926faf created.
[INFO] INFO     2015-05-29 14:01:21,921 module.py:1745] New instance for module "default" serving on:
[INFO] http://localhost:8080
[INFO] 
[INFO] ERROR    2015-05-29 14:01:21,923 module.py:872] Request to '/_ah/start' failed
[INFO] INFO     2015-05-29 14:01:21,923 module.py:788] default: "GET /_ah/start HTTP/1.1" 500 -
[INFO] INFO     2015-05-29 14:01:21,924 health_check_service.py:101] Health checks starting for instance 0.
[INFO] ERROR    2015-05-29 14:01:21,926 module.py:872] Request to '/_ah/health' failed
[INFO] INFO     2015-05-29 14:01:46,606 module.py:788] default: "GET /index.html HTTP/1.1" 404 -
[INFO] INFO     2015-05-29 14:01:50,401 module.py:788] default: "GET / HTTP/1.1" 302 -
^[d[INFO] INFO     2015-05-29 14:02:58,028 module.py:788] default: "GET / HTTP/1.1" 500 436
[INFO] INFO     2015-05-29 14:03:51,561 module.py:788] default: "GET / HTTP/1.1" 500 436
[INFO] INFO     2015-05-29 14:04:46,156 module.py:788] default: "GET / HTTP/1.1" 500 436
[INFO] INFO     2015-05-29 14:06:40,599 module.py:788] default: "GET / HTTP/1.1" 302 -

I'm using ubuntu vivid (15.04), java (oracle) 1.8.0, docker 1.6.