Upgrade a repository, branch or working tree to a newer format.


brz upgrade [URL]


Remove the backup.bzr directory if successful.


Show what would be done, but don’t actually do anything.

-h, --help

Show help message.

-q, --quiet

Only display errors and warnings.


Show usage message and options.

-v, --verbose

Display more information.

Branch format:

Upgrade to a specific format. See “brz help formats” for details.

--2a, --bzr, --default

Format for the bzr 2.0 series.


GIT repository.


Bare GIT repository (no working tree).


When the default format has changed after a major new release of Bazaar/Breezy, you may be informed during certain operations that you should upgrade. Upgrading to a newer format may improve performance or make new features available. It may however limit interoperability with older repositories or with older versions of Bazaar or Breezy.

If you wish to upgrade to a particular format rather than the current default, that can be specified using the –format option. As a consequence, you can use the upgrade command this way to “downgrade” to an earlier format, though some conversions are a one way process (e.g. changing from the 1.x default to the 2.x default) so downgrading is not always possible.

A backup.bzr.~#~ directory is created at the start of the conversion process (where # is a number). By default, this is left there on completion. If the conversion fails, delete the new .bzr directory and rename this one back in its place. Use the –clean option to ask for the backup.bzr directory to be removed on successful conversion. Alternatively, you can delete it by hand if everything looks good afterwards.

If the location given is a shared repository, dependent branches are also converted provided the repository converts successfully. If the conversion of a branch fails, remaining branches are still tried.

For more information on upgrades, see the Breezy Upgrade Guide, https://www.breezy-vcs.org/doc/en/upgrade-guide/.

See also

check, formats, reconcile