Connect MinIO with Blob0

Connect Blob0 on Mac to an existing MinIO bucket. Get the S3 API endpoint, signing region and restricted keys from your administrator, then test listing access and save the connection.

Use this guide when your MinIO server and bucket already exist. Blob0 connects to the S3 API for object work; it does not install or administer the server.

Download and installation guide

Before you connect

Have an existing bucket and a key pair issued by the MinIO administrator, scoped to that bucket and the actions you need. The key must be allowed to list the bucket root for Test connection.
Get the endpoint and signing Region for this deployment from its administrator. Leave the optional Public / custom domain field blank unless a direct-link domain has already been configured.

Provider configuration notes

Use the server’s S3 API address in Blob0, not its Console URL. Port examples are only starting points; use the address and connection settings supplied for your deployment.

S3 API endpoint, not Console: The S3 API handles object requests; the Console is a separate web interface. The API default is port 9000. The Console port can be assigned dynamically; 9001 is a common explicitly configured example, not a guaranteed default. Enter the API URL and keep the bucket name in its own field.
Use the address reachable from this Mac: http://localhost:9000 is only an example for a MinIO server running on the same Mac. For a remote server, ask the administrator for its reachable DNS or proxy URL and confirm the network route and TLS certificate work from this Mac.
Match region and URL style: The MinIO preset starts with Region us-east-1 and path-style addressing. Region must match the server deployment; keep path-style or switch it only as required by that service’s endpoint configuration.
Ask for restricted access keys: Use an Access Key ID and Secret Access Key issued by the server administrator and scoped to the bucket and actions you need. Blob0 stores the keys in macOS Keychain; the profile keeps non-sensitive connection details.

The server operator controls MinIO users, policies, network exposure, and TLS. Blob0 can connect only when the supplied S3 API endpoint is reachable and the keys are authorized.

Provider-specific limits

Connect to a server that is already deployed. Blob0 does not install, update, or administer MinIO servers, users, or policies.
Blob0 is a graphical client that also ships a blob0 command line for everyday object operations. It does not replace mc’s cluster or administration features and does not mount a bucket in Finder.
Server access, TLS, credentials, and bucket permissions remain under the MinIO operator’s control.

Fill in the Blob0 connection form

On first launch, use the connection form. To add another bucket later, open Settings → Connections → Add connection. Choose MinIO under Provider, then replace the examples below with the values supplied for your deployment. Do not include the bucket name in the endpoint.

Fill in the Blob0 connection form
App field	What to enter
Provider	MinIO
Connection name	A local label, such as Team MinIO. It does not rename the bucket.
S3 API endpoint	https://storage.example.com (example only; replace with the reachable S3 API URL from your administrator). Do not use the Console URL.
Bucket	example-documents (example only; replace with the exact existing bucket name). Do not enter a URL or folder prefix.
Region	The server signing Region. The MinIO preset starts at us-east-1; confirm the value with the operator.
Access Key ID	The bucket-scoped key ID issued by the MinIO administrator.
Secret Access Key	The secret paired with that key ID. Enter it only in Blob0; it is stored in macOS Keychain.
Public / custom domain	Optional. Leave blank for a private bucket; this field does not affect API authentication.
Use path-style URLs	The MinIO preset starts with path-style enabled. Keep it unless the administrator says this endpoint requires virtual-hosted addressing.

Blob0 connection form with fictional settings: Connect MinIO with Blob0 — Real application interface with fictional settings; no usable credentials are shown.

Test and save the connection

Test connection
Select Test connection. Blob0 lists the selected bucket at its root and may show 0 items for an empty bucket. A successful result confirms only that this listing request succeeded; it does not prove access to object contents or permission to upload, overwrite, or delete.
The MinIO preset starts with path-style enabled. If the listed objects do not appear, first confirm that the bucket name and key scope match; then compare the endpoint path style with the administrator’s service configuration.
Add connection
After the test succeeds, select Add connection to save the profile and connect. Blob0 stores access keys in the macOS Keychain; the profile keeps non-sensitive connection details.

Optional: verify an authorized transfer

Only if the bucket owner has authorized write testing, upload a tiny temporary file under a new test name, download it and compare its contents, then delete that exact test object. Check the bucket policy and retention rules first; never use an existing object as the test file.

Troubleshooting

AccessDenied: Confirm the key is active, scoped to this bucket, and allowed to list the bucket root. Ask the operator to check the applicable user and bucket policies.
SignatureDoesNotMatch: Check that Access Key ID and Secret Access Key belong together, that Region matches the server signing configuration, and that the Mac clock is accurate.
NoSuchBucket or 404: Copy the exact bucket name and confirm that the endpoint points to the same MinIO deployment. The Bucket field takes a name, not a URL or prefix.
Endpoint or TLS error: Confirm this Mac can reach the S3 API hostname and port, and that its TLS certificate is trusted. A Console address or Console port cannot substitute for the S3 API endpoint.
Addressing or proxy error: Keep path-style enabled unless the operator documents another URL style. Ask the operator to verify that the proxy routes S3 API paths to the API service.

Continue with Blob0

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