Umpire, standing for Unified MES Proxy, Imaging, and Reimaging Engine, is an unified service management framework to serve Chrome devices' manufacturing process, including image downloading, factory testing, finalization, and uploading of events and reports.

Umpire is created as a daemon with command-line tool. A web-based management console (with better deployment process) is created as standalone project Dome.

Umpire controls what it serves by JSON configuration file. To make changes, you can do umpire edit. After editing, it automatically runs command umpire deploy so the new configuration is activated.

Data generated (or the resources to be delivered) are stored in /var/db/factory/umpire/..... inside Docker, and /cros_docker/umpire/$PROJECT/..... outside Docker.


  1. You need Docker installed on the target computer. Read Factory Server for more details.


Umpire is one of the component bundled in Chrome OS Factory Server package, so please follow the steps in Factory Server.

Using Umpire

Umpire can be configured using Dome which provides a web interface. Please follow Dome user guides to access Umpire.

Trouble shooting

This section is for advanced developers, to access Umpire directly without using Dome.

Check if Umpire is running properly

Enter Docker instance shell and do umpire status.

setup/ umpire shell
 umpire status

A typical output:

Active config:

Deploy a factory bundle

Umpire by default comes with empty bundle. To feed the images (with test image, release image, toolkit, firmware, hwid, ... etc) you have to first prepare it with the finalize_bundle command. When a bundle file is available, do:

sudo cp /cros_docker
setup/ umpire shell
 umpire import-bundle /mnt/
 umpire edit  # and mark the bundle in rulesets as active.

Update resources

You have to first copy the new file into /cros_docker (which can be found as /mnt inside Docker) then notify Umpire to use them using umpire update command. Example:

setup/ umpire shell
 umpire update --from 20150702_rev3 --to 20150702_rev3_newtoolkit \
 umpire edit

You should see a new bundle name 20150702_rev3_newtoolkit. Put it in ruleset section and active it.

To update HWID:

umpire update --from 20150702_rev3 --to 20150702_rev3_newhwid hwid=./hwid.gz

There are also resources:

  • hwid: HWID bundle (could be gzipped).
  • firmware: The chromeos-firmware script (could be gzipped).
  • toolkit: The toolkit file (


The Docker containers were configured to auto-restart if your machine was rebooted unexpectedly. If you want to fully restart Umpire, try setup/ umpire stop, setup/ umpire run.

Change configuration

To configure additional services, enter Docker and execute umpire edit to get additional commands.

A sample configuration (in JSON) looks like:

  "bundles": [
      "id": "empty",
      "note": "n/a",
      "payloads": "payload.99914b932bd37a50b983c5e7c90ae93b.json"
  "rulesets": [
      "active": true,
      "bundle_id": "empty",
      "note": "n/a"
  "services": {
    "shop_floor": {
      "service_url": "http://localhost:8090"

Rule-based Update

The most important advantage of using Umpire server is supporting of “rule-based update”. For example:

- bundle_id: 20140909_proto0_smt_update
  note: SMT test list should be OK
  active: true
    device_factory_toolkit: [~, ~]
    rootfs_release: [GRT, SMT]
    rootfs_test: [GRT, SMT]
    firmware_ec: [GRT, SMT]
    firmware_bios: [GRT, SMT]

Get logs

There are two places for logs of Umpire.

  1. Services hosted by Umpire, especially shop floor proxy. The logs are accessible outside Docker. Find them in /cros_docker/umpire/$PROJECT/log.

    For example, nginx logs are in:

    cd /cros_docker/umpire/$PROJECT/log
    less httpd_access.log
    less httpd_error.log
  2. Umpire itself. Logs are handled by Docker.

    docker logs umpire_$PROJECT