Connect Backblaze B2

Add B2 as a routing target for archive and low-cost storage.

BlobRouter v0.1 · Last updated: August 2026 · Architecture version: 2.0

Backblaze B2 is the preferred destination for priority: "archive" uploads — low storage cost for rarely accessed data.

Prerequisites

• A Backblaze account
• A B2 bucket
• An application key with access to that bucket

1. Create a bucket

1. Backblaze → Buckets → Create a Bucket
2. Choose a private bucket
3. Note the bucket name and region (for example us-west-004)

2. Create an application key

1. App Keys → Add a New Application Key
2. Restrict to your bucket if possible
3. Copy keyID (access key) and applicationKey (secret)

S3-compatible endpoint:

https://s3.<region>.backblazeb2.com

Example: https://s3.us-west-004.backblazeb2.com

3. Add credentials in BlobRouter

1. Open Dashboard → Providers
2. Choose Backblaze B2
3. Enter Access Key ID, Secret Access Key, bucket name, and region
4. Save and Test connection

4. Upload with archive priority

import { BlobRouter } from "@blobrouter/sdk";
import { readFileSync } from "fs";

const storage = new BlobRouter({
  apiKey: process.env.BLOBROUTER_API_KEY,
});

const file = readFileSync("./checkpoint.bin");

const result = await storage.upload(file, {
  fileName: "checkpoint.bin",
  contentType: "application/octet-stream",
  fileSizeBytes: file.length,
  priority: "archive",
});

console.log(result.provider); // "backblaze-b2" when B2 is configured

Troubleshooting

Symptom	Fix
403 on test / upload	Key lacks bucket permission, or wrong region/endpoint
Routes away from B2 with warning	Confirm B2 is saved under Providers
Path-style issues	BlobRouter uses path-style S3 clients; keep the regional s3.<region>.backblazeb2.com endpoint