Limits

Storage zone, connection, rate, request, and naming limits for Bunny Storage.

To ensure optimal performance for all users, Bunny Storage enforces limits on concurrent connections, request rates, throughput, and file naming. This page describes the limits that apply to your storage zones and how to work within them.

How limits are applied

Most limits are applied on a per-server basis. Each Bunny Storage region runs multiple servers, and each server tracks limits independently.

In practice, this allows you to achieve much higher concurrency than the per-server limits suggest.

Connection limits

Limit	Value	Description
Concurrent HTTP connections per IP	100	Per server, per remote IP. Shared across the S3-compatible and HTTP APIs combined.
Concurrent FTP connections per IP	250	Per server, per remote IP.
Simultaneous FTP commands per IP / zone	300	Per server. Maximum number of FTP commands that can be in flight at once.

Request limits by operation

Certain operations have their own concurrency and size limits:

Operation	Limit
POST (zip or download requests)	10 requests per zone
POST maximum request body size	8 MB
Folder listing (HTTP GET and FTP)	5 requests at a time
DELETE	30 simultaneous requests

HTTP API limits

The HTTP API is limited to 250 concurrent connections per zone, per server. Connections beyond this limit are rejected until capacity frees up.

S3 API throughput and rate limits

Limit	Value	Description
Throughput per connection	1 Gbps	Maximum bandwidth for a single connection.
Requests per second	500 RPS	Maximum sustained request rate per storage zone.

To move data faster than a single connection allows, split transfers across multiple parallel connections rather than relying on one.

Rate limit responses

The response you receive depends on which limit you reach and which protocol or API you’re using.

Limit reached	Protocol / API	Response
IP concurrency limit	HTTP	429 Too Many Requests
IP concurrency limit	FTP	421 Too many connections (N) from this IP, please try again later
IP concurrency limit	S3 API	503 SlowDown, with a Retry-After: 5 header
Concurrent connections per zone (250)	HTTP	429 Too Many Requests
Concurrent connections per zone (250)	FTP	Connection refused
Concurrent connections per zone (250)	S3 API	503 SlowDown, with a Retry-After: 5 header
Per-operation concurrency (GET / POST / DELETE)	HTTP	400 Unable to process request
Folder listing rate limit	HTTP	400 Unable to process request
Folder listing rate limit	FTP	421 Server busy, please try again later

For the per-IP FTP response, N is the number of connections currently open from your IP.

If you hit one of these limits:

1. Reduce concurrent connections
2. Implement exponential backoff retry logic (and honor the Retry-After header when present)
3. Distribute requests across longer time periods

File and directory naming

When naming files and folders in Bunny Storage:

• A file name including its full path cannot exceed 6,000 characters.
• A directory path cannot exceed 6,000 characters.
• File names cannot start or end with a space, and cannot be empty.

Uploads that violate these rules are rejected.

SFTP path restrictions

For security, SFTP paths cannot contain .. (parent-directory traversal). If a path includes .., the SFTP connection fails silently, with no error message. If your SFTP client stops working unexpectedly, check that none of your paths contain ...

Renaming files

Renaming files or folders directly on Bunny Storage is not currently supported by design, so you won’t see a rename option in the dashboard or over FTP. Allowing renames could cause inconsistencies while content propagates across edge locations, so the action is blocked to keep replication stable.

To rename a file, re-upload it under the new name, then delete the old one once the upload succeeds.

Durability and reliability

For information about data durability, redundancy, and reliability guarantees, see Durability.