FR: 
There are instructions for rollback of prod also: https://sites.google.com/a/google.com/chromeos/for-team-members/infrastructure/chromeos-admin/push-to-prod#TOC-Rolling-Back-a-Prod-Push

... but they're known to not work.

Is it possible / worthwhile to also:
- have deploy_servers.py reset a 'prod-last' to 'prod' before moving 'prod'. This way, we leave a ref of the rollback target if we want to do that.
- Add a flag '--rollback' to deploy_servers.py to update prod back to prod-last instead of going forward to 'prod-next'.

wdyt?

Issue 657887 has been merged into this issue.

+akeshet: Do you think investing in rollback is worthwhile here? Most pushes should theoretically be safe to rollback (db updates are exceptions).

I think investing in rollback is a lower priority than other work.

The automation part has been fixed. If there is a feature request for the rollback, feel free to open a separate one for this.