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Heroku retains daily backups for 7 days, and weekly backups for 4 weeks. (more details re: retention schedule)
Options
a) Rake task: Replace the Ansible-managed scriptpostgres-backup.sh with a rake task run regularly on a one-off Heroku dyno. This would obtain the latest database URL and then push it up to s3, where it can wait to be harvested by the Dubnium script.
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