Apache HTTP Server Version 2.5

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# Apache Module mod_ratelimit

Description: | Bandwidth Rate Limiting for Clients
Status: | Extension
Module Identifier: | ratelimit_module
Source File: | mod_ratelimit.c
Compatibility: | `rate-initial-burst` available in httpd 2.4.24 and later. Rate limiting proxied content does not work correctly up to httpd 2.4.33.

### Summary

Provides a filter named `RATE_LIMIT` to limit client bandwidth. The throttling is applied to each HTTP response while it is transferred to the client, and not aggregated at IP/client level. The connection speed to be simulated is specified, in KiB/s, using the environment variable `rate-limit`.

Optionally, an initial amount of burst data, in KiB, may be configured to be passed at full speed before throttling to the specified rate limit. This value is optional, and is set using the environment variable `rate-initial-burst`.

### Example Configuration

    <Location "/downloads">
        SetOutputFilter RATE_LIMIT
        SetEnv rate-limit 400
        SetEnv rate-initial-burst 512
    </Location>

If the value specified for `rate-limit` causes integer overflow, the rate-limited will be disabled. If the value specified for `rate-limit-burst` causes integer overflow, the burst will be disabled.

### Directives

This module provides no directives.

### Bugfix checklist

- httpd changelog
- Known issues
- Report a bug