Connect Backblaze B2

Backblaze B2 offers an S3-compatible API at low storage cost. Plume builds the endpoint from your bucket’s region.

1. Create an application key

1. In the Backblaze console, create a bucket under Buckets. Set it to public if visitors will load files directly.
2. Note the region in the bucket’s endpoint URL. It looks like s3.us-west-004.backblazeb2.com, so the region is us-west-004.
3. Open App Keys and create a new application key. Limit it to your bucket and allow read and write.
4. Copy the keyID and the applicationKey. The application key is shown once.

Use an application key from App Keys. Your account ID and master key are not what Plume expects.

2. Fill in the setup wizard

Open Media → Plume and choose Backblaze B2.

Field	Where to find it
Bucket	The bucket name from the Buckets page.
Region	Visible in the bucket endpoint URL, for example us-west-004 or eu-central-003.
Application Key ID	Create one under App Keys in the Backblaze console. This is the keyID, not your account ID.
Application Key	The applicationKey. Shown once when you create it.
Path Prefix (optional)	A folder inside the bucket, for example media.
Custom Endpoint (optional)	Leave empty. Plume builds https://s3.<region>.backblazeb2.com.
Custom Domain (optional)	A CDN or custom domain for public URLs.

3. Test and offload

Open Tools and select Test Connection. A working setup reports that the connection succeeded and write access is verified. Then run Offload existing library under Bulk media jobs, or queue files from the command line:

wp nimbus sync --limit=500
wp nimbus process-pending --limit=500

sync marks attachments as pending. process-pending offloads them. See bulk migration for details.

Notes

• Path-style requests are off for B2. Plume sets this for you.
• If you serve images through Cloudflare, set the Custom Domain to your proxied hostname. See custom domain and CDN.

Tip: Create a separate application key for Plume and restrict it to one bucket.