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In heroku CLI , run heroku maintenance:on -a scihist-digicoll-production and heroku maintenance:off -a scihist-digicoll-production
(Note: This uses a customized maintenance page in an S3 bucket, as stored in heroku config var MAINTENANCE_PAGE_URL per instructions at https://devcenter.heroku.com/articles/maintenance-mode#customizing-your-maintenance-page Note that S3 needs to be there, if it’s missing, may get a blank maintenance page. There seems to be no way to switch back to heroku default maintenance page, per possible heroku bug). See more on our custom maintenance page configuration at Heroku custom maintenance page )
Disable staff logins
We can effectively make the app “read-only” but still available to the public by disabling staff logins. So we don’t have a public facing outage, but if we’re dealing with some kind of data corruption issue we’re trying to diagnose, we might want to ‘freeze’ staff out.
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