MongoDB

Managed MongoDB with replica sets, automated backups, and private cluster networking.

Creating a MongoDB instance

From the dashboard, click New service → Database → MongoDB. Choose MongoDB 7.x, a storage size (1 GB to 500 GB), and a plan. StackBlaze provisions a StatefulSet and initializes the replica set automatically.

Attach MongoDB to your service from the Environment tab. StackBlaze injects MONGODB_URL automatically.

Connection strings

Internal (recommended)

mongodb://user:password@[service-name]:27017/dbname

Replica set connection (Pro+)

On Pro and Enterprise plans, MongoDB runs as a 3-node replica set. Use the replica set connection string to enable automatic failover and read preference configuration.

mongodb://user:password@[service-name]-0:27017,[service-name]-1:27017,[service-name]-2:27017/dbname?replicaSet=rs0&authSource=admin

External (for Compass / mongosh)

Use the external connection string for MongoDB Compass or mongosh from your local machine. Find it in Settings → Connection.

mongosh "mongodb+srv://user:password@cluster.stackblaze.cloud/dbname"

Replica sets

Plan	Topology	Failover
Free	Single node (no replica set)	None
Starter	Single node (no replica set)	None
Pro	3-node replica set	Automatic (under 30s)
Enterprise	3-node replica set + hidden secondary	Automatic (under 30s)

With a 3-node replica set, MongoDB automatically elects a new primary if the current primary becomes unavailable. Your application should use the replica set connection string and enable retryable writes for seamless failover.

import mongoose from 'mongoose'

await mongoose.connect(process.env.MONGODB_URL, {
  retryWrites: true,
  w: 'majority',
  readPreference: 'primaryPreferred',
})

Automated backups

All plans include daily automated snapshots, and you can take an on-demand snapshot at any time before a risky change. Backups are encrypted at rest and stored separately from your primary data. Restore to a new instance without interrupting your live database from Backups → Restore.

Plan	Snapshot retention
Free	1 day
Starter	3 days
Pro	7 days
Enterprise	30 days

Indexes

Create indexes in your application startup code or migration scripts. For production deployments, always create indexes with { background: true } (MongoDB before 4.2) or as a rolling build to avoid blocking reads and writes on large collections.

// In your model definition
const userSchema = new mongoose.Schema({
  email: { type: String, unique: true, index: true },
  createdAt: { type: Date, index: true },
  'profile.city': { type: String },
})

// Compound index
userSchema.index({ 'profile.city': 1, createdAt: -1 })

// Text search index
userSchema.index({ name: 'text', bio: 'text' })

Connecting with common ODMs

Mongoose

import mongoose from 'mongoose'

if (mongoose.connection.readyState === 0) {
  await mongoose.connect(process.env.MONGODB_URL!, {
    serverSelectionTimeoutMS: 5000,
    socketTimeoutMS: 45000,
  })
}

Prisma (MongoDB provider)

datasource db {
  provider = "mongodb"
  url      = env("MONGODB_URL")
}

model User {
  id    String @id @default(auto()) @map("_id") @db.ObjectId
  email String @unique
  name  String
}

Motor (Python async)

from motor.motor_asyncio import AsyncIOMotorClient
import os

client = AsyncIOMotorClient(os.environ["MONGODB_URL"])
db = client.get_default_database()