gsutil FAQ

gsutil is a command line tool for working with Google Storage (GS) buckets. We use it heavily in ChromiumOS to mirror our files around the world.

See the official gsutil Tool documentation for more details.

This document is a practical guide for our developers working with GS.

Installing gsutil

The easiest way to run gsutil on your workstation is to use the copy that is part of the CrOS checkout in chromite. Simply run ~/chromiumos/chromite/scripts/gsutil to get an up-to-date version. You can symlink that into your personal $PATH to simplify things.

Otherwise, feel free to follow the official Install gsutil documentation.

Configure authentication (.boto)

If you don't have a ~/.boto file set up yet for your account, you can use the config subcommand to do so. It will print out directions for you to follow.

For Googlers, make sure to use your account. Otherwise, you'll see auth errors trying to access non-public buckets.

When prompted for a project ID, enter chromeos-bot (this is the main ChromeOS project ID).

(outside) $ ~/chromiumos/chromite/scripts/gsutil config

Various GS buckets

There are a variety of GS buckets that show up in CrOS. We try to cover everything that CrOS developers might see.

As a general rule, buckets that start with gs://chromeos- are not browseable by the public, although some files might be readable for tools to access.

Buckets that start with gs://chromiumos- are fully readable by the public. Do not host any internal files on such buckets.

Note: We omit buckets that are already documented in Archive Mirrors.

Build/Release buckets

These buckets are used by our builders and release process.

cros flash and cros chrome-sdk will pull artifacts from these buckets.

  • gs://chromeos-image-archive/ (all internal unsigned artifacts): All CrOS builders write their outputs/artifacts to this bucket. No signed images are stored here.
    • $BOT_CONFIG_NAME/$CROS_VERSION/: Each bot config gets a unique directory, and each build has a unique version.
  • gs://chromiumos-image-archive/ (all public unsigned artifacts): Like the chromeos-image-archive bucket above, but for public builders.
  • gs://chromeos-releases/ (only signed artifacts): After CrOS builders upload to gs://chromeos-image-archive/, they copy some of the images to this bucket for signing. The signer then downloads those, signs them, and then uploads new (now signed) files.
    • $CHANNEL-channel/$BOARD/$CROS_VERSION/: Each channel is independent, as is the board and version.
  • gs://chromeos-releases-public/: Used for hosting OS updates. Only used by release engineers.

Public artifacts

These buckets are automatically updated by builders for public consumption.

  • gs://chromiumos-sdk/: The ChromeOS SDK itself and standalone toolchains. The SDK tarballs live in the top directory while toolchains live in dated subdirectories.
  • gs://chromeos-dev-installer/: Prebuilts for the dev_install command for quickly installing developer packages on release images in dev mode.
  • gs://chromeos-prebuilt/: Various prebuilt (e.g. binpkgs) for quickly building & updating boards and the SDK.

Testing buckets

These aren't used for anything other than testing. Code should not rely upon these for anything other than testing.

  • gs://chromeos-releases-test/: Used for release/paygen/signing network based testing. Content is not guaranteed to have a long life. Attempts to get official/mp key signed artifacts here will be rejected.
  • gs://chromeos-throw-away-bucket/: Writable by anyone in Google. Useful for network based unittests without worrying about breaking things. Content is not guaranteed to have a long life.

Android (ARC++) buckets

These are used by developers working on ARC++ (Android in CrOS).

  • gs://android-build-chromeos/: Candidate prebuilt Android images generated continuously by the Android infrastructure. The CrOS infrastructure, after verifying them via the Android PFQ (and cros_mark_android_as_stable), will copy the files over to gs://chromeos-arc-images/ for releases. Note: Files in here have a limited lifespan and cannot be relied upon for long term storage.
  • gs://chromeos-arc-images/: Prebuilt Android images referenced by official ARC++ ebuilds for use in CrOS releases.

VM/container (Crostini) buckets

These buckets are used for Containers/VM/Crostini.

  • gs://chrome-component-termina/: Termina VM images for signing. VM images uploaded here will be signed, then made available in the Omaha dashboard for release.
  • gs://termina-component-testing/: Termina VM images for testing. This bucket contains both the live and staging VM images.
  • gs://cros-containers/: LXD container images.
  • gs://cros-containers-staging/: Staging LXD container images. Used only in testing.
  • gs://cros-packages/: apt package repo for container guests.
  • gs://cros-packages-staging/: Staging apt package repo for container guests. Used only in testing.

ClusterFuzz buckets

See the fuzzing documentation for details on the buckets used by ClusterFuzz.

Old/dead buckets

These buckets are no longer used by current systems.

  • gs://chromeos-bcs/: Precursor to gs://chromeos-binaries/ when BCS (Binary Component Server) was a ssh/ftp box rather than GS bucket. Used by developers and partners to host random (usually firmware) files.

googlestorage_acl.txt file format {#googlestorage_acl.txt}

The googlestorage_acl.txt file is used to set permissions for files associated with a particular overlay/board/project. It is a series of arguments that are passed to the gsutil acl ch command. Comments start with a # character and extend to the end of the line.

# For information about this file, see

# Give owners of the project full control.
-g 00b4903a97fb6344be6306829e053825e18a04ab0cc5513e9585a2b8c9634c80:FULL_CONTROL

# Give viewers of the project read access.
-g 00b4903a97ce95daf4ef249a9c21dddd83fdfb7126720b7c3440483b6229a03c:READ

# Give all Googlers read access.


How do you set up prebuilts for a new private overlay?

Add a googlestorage_acl.txt file in the root of the private overlay.

How do I create a new GS bucket?

Creating a new GS bucket is not normally something we do. You should double check to see if any of the existing buckets satisfy your use case, and if not, be prepared to provide extensive justification.

If you're confident you need a new bucket, please file a bug using the Infra>Client>ChromeOS component.