MinIO¶

What it is¶

MinIO is a high-performance, S3-compatible object storage server. It is built for large-scale AI/ML data infrastructure and cloud-native applications.

What problem it solves¶

It provides a way to host your own S3-compatible storage on-premises or in private clouds, offering the same API as Amazon S3 but with full control over the infrastructure and data.

Where it fits in the stack¶

Intake & Storage. It acts as the object storage layer for storing unstructured data like images, videos, log files, and model artifacts.

Typical use cases¶

Storing large datasets for AI model training.
Providing S3-compatible storage for self-hosted applications (e.g., Nextcloud, GitLab).
Building a private "data lake" for enterprise analytics.
Serving as a backup target for various systems.

Strengths¶

High performance (capable of hundreds of gigabytes per second).
100% S3 compatible API.
Cloud-native and container-friendly.
Built-in data protection (Erasure Coding, Bitrot protection).

Limitations¶

Managing large clusters requires significant infrastructure knowledge.
Not a block storage or file system replacement (optimized for object storage).

When to use it¶

When you need high-performance object storage and want to avoid cloud lock-in.
For local development where you need an S3 API without paying for AWS.

When not to use it¶

For simple file sharing (consider Nextcloud or Syncthing).
If you only need a small amount of storage and prefer a managed service (consider Storj or Amazon S3).

Licensing and cost¶

Open Source: Yes (GNU AGPLv3)
Cost: Free (Community), Paid (Enterprise Support)
Self-hostable: Yes

Getting started¶

Docker¶

Run a single-node MinIO server using Docker:

docker run -p 9000:9000 -p 9001:9001 \
  -e "MINIO_ROOT_USER=AKIAIOSFODNN7EXAMPLE" \
  -e "MINIO_ROOT_PASSWORD=wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY" \
  -v /mnt/data:/data \
  quay.io/minio/minio server /data --console-address ":9001"

Hello World¶

Access the MinIO Console at http://localhost:9001.
Log in with the MINIO_ROOT_USER and MINIO_ROOT_PASSWORD defined above.
Click Create Bucket and name it test-bucket.
Click Upload to add a file to your new bucket.
You now have a functional S3-compatible storage server!

CLI examples¶

The mc (MinIO Client) tool is the standard way to manage MinIO and other S3-compatible services.

# Add a server alias
mc alias set myminio http://localhost:9000 AKIAIOSFODNN7EXAMPLE wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY

# List buckets
mc ls myminio

# Mirror a local directory to a bucket
mc mirror ./my-local-data myminio/test-bucket

# Set an anonymous policy (public read) on a bucket
mc anonymous set download myminio/test-bucket

API examples¶

Use the boto3 library (Python) or the official MinIO SDKs.

Python (Boto3)¶

import boto3

s3 = boto3.client(
    "s3",
    endpoint_url="http://localhost:9000",
    aws_access_key_id="AKIAIOSFODNN7EXAMPLE",
    aws_secret_access_key="wJalrXUtnFEMI/K7MDENG/bPxRfiCYEXAMPLEKEY"
)

# Upload a file
s3.upload_file("test.txt", "test-bucket", "test.txt")

# Download a file
s3.download_file("test-bucket", "test.txt", "downloaded_test.txt")

Sources / References¶

Contribution Metadata¶

Last reviewed: 2026-04-28
Confidence: high