JustFans docs

Guide

Backblaze B2

Backblaze B2 is S3-compatible, so it can be used as a storage driver for uploaded images, videos, avatars, covers, and other user assets.

In the admin panel, select Backblaze B2 under Admin > Settings > Storage > Driver.

Create the bucket

  1. Sign in to Backblaze and make sure B2 Cloud Storage is enabled on your account.
  2. Go to B2 Cloud Storage > Buckets and create a new bucket.
  3. Set the bucket type to Public if uploaded files should be served directly by the site or through a CDN.
  4. After the bucket is created, open its details and copy the S3 endpoint. It looks like: https://s3.us-east-005.backblazeb2.com.

Create an application key

  1. Go to B2 Cloud Storage > Application Keys.
  2. Create a new key. You can allow access to all buckets, or restrict it to the bucket you created for the site.
  3. If you restrict the key to one bucket, enable Allow List All Bucket Names. This helps S3-compatible tools and the storage validation check list the bucket correctly.
  4. Copy the keyID and applicationKey. The application key is shown only once.

Fill in the admin settings

In Admin > Settings > Storage, select Backblaze B2 and fill in:

  • Application key ID: the Backblaze keyID.
  • Application key: the Backblaze applicationKey.
  • Bucket name: your B2 bucket name.
  • Region: the region from the endpoint, for example us-east-005.
  • Endpoint URL: the full S3 endpoint, for example https://s3.us-east-005.backblazeb2.com.
  • Custom URL: optional. Use this only if you serve the bucket through a CDN or custom domain, for example https://media.yourdomain.com.

Allow your site in CORS rules

Backblaze B2 also needs a CORS rule for your website domain. Without it, public files may upload correctly, but admin previews, file manager assets, or browser-based asset requests can fail because the browser blocks cross-origin access.

  1. In Backblaze, open your bucket and click CORS Rules.
  2. Choose Share everything in this bucket with this one origin.
  3. Enter your site origin, for example https://yourdomain.com. Use only the scheme and domain, without a path.
  4. If your admin panel is served from a different subdomain, add that origin too. For example, add https://admin.yourdomain.com if the public site and admin panel do not share the same origin.
  5. If you are using a CDN or custom storage URL, make sure the CDN/custom domain is also allowed wherever your setup requires browser access.

Notes:

• Backblaze B2 controls public access at the bucket level. If the bucket is private, public media URLs will not load unless you put a signed/CDN layer in front of it.
• For CDN delivery, Backblaze commonly supports Cloudflare and Fastly in front of B2. Add the CDN/custom domain to Custom URL only after it is working.
• The endpoint should not include the bucket name. Use https://s3.<region>.backblazeb2.com.
• CORS changes can take a short time to apply. If admin previews still fail, wait a minute and refresh the admin page.