Make an S3 bucket safe for Eigen

When Eigen stores files in an S3 bucket, it writes the whole file again on every save. If the bucket has no versioning, the previous copy is replaced and nothing can bring it back. The Bucket safety panel tells you where the bucket stands and can set it right for you.

Only the server owner can reach these settings.

Open the panel

1. Sign in as the owner and go to Admin, then click Settings in the sidebar.
2. Under Defaults, set Storage Type to S3 Bucket. The S3 Configuration form appears.
3. Fill in Endpoint, Bucket, Region, Access Key ID, and Secret Access Key. Fill in Prefix as well if your files live under a path inside the bucket.
4. Click Test Connection.
5. When the test reports that the connection worked, the Bucket safety panel appears below the form.

The same S3 Configuration form, with the same panel, appears when you give a team its own storage. Open the team from Teams in the sidebar, then click Add in the Mounts section to reach Add Mount, or Mount settings on a mount that is already there to reach Edit Mount.

What the panel tells you

The panel shows two lines, each with a tick or a warning sign.

Versioning is the one that protects your files:

The line says	What it means
Versioning: on	Old copies are kept, so an overwrite or a delete can be undone.
Versioning: off. Overwrites are permanent.	The moment a file is saved over or deleted, the old copy is gone.
Versioning: suspended. New overwrites are permanent.	Versions from before are still there, but nothing new is kept.
Versioning: cannot be read with this access key.	The key does not have permission to read the bucket's settings.

Old-version cleanup is about cost. Eigen re-uploads the whole file on every save, so a document someone works on all day leaves a lot of old versions behind. A cleanup rule removes them after a set number of days:

The line says	What it means
Old-version cleanup: expires versions after 30 days	A rule is in place, and this is how long old versions are kept.
Old-version cleanup: no rule. Old versions grow forever.	Nothing removes old versions, and you keep paying for all of them.
Old-version cleanup: another lifecycle rule is in place.	The bucket has a rule that Eigen did not write, and Eigen never overwrites one of those.
Old-version cleanup: cannot be read with this access key.	The key does not have permission to read the bucket's settings.

Turn on safe defaults

1. Click Enable safe defaults at the top of the panel.
2. The Make this bucket safe for Eigen window opens. Under Expire old versions after, set how many days old versions are kept. It starts at 30, and you can set anything from 1 day to 3650 days.
3. Click Enable.

Eigen turns on versioning and adds one cleanup rule, then reads the bucket back and writes what it changed under the two lines. Versioning applies to the whole bucket. The cleanup rule covers only the path in Prefix, if you set one, so it leaves anything else in the bucket alone.

More days means a longer window to recover from, and more storage to pay for. Thirty days is a reasonable starting point for most servers.

Change how long versions are kept

Once both lines have a tick, the button is gone. Click Change at the end of the Old-version cleanup line, set a new number of days in the window that opens, and click Update.

Set the bucket up by hand

Some access keys are allowed to read and write files but not to change bucket settings. In that case, and when the bucket already has a lifecycle rule of its own, the panel shows the same settings as aws commands. Click Copy commands and run them against the bucket yourself, from a machine where the AWS command-line tool is set up for that provider.

The panel fills the commands in with your endpoint, bucket, prefix, and the number of days you picked. Keep the rule's ID as it is. Eigen recognises its own rule by that ID, so a rule under a different name reads as somebody else's and is left alone.

Check it later

Come back to Settings, click Test Connection again, and read the two lines. They are read from the bucket each time, so they always show what the bucket says right now, not what you set last month.