---
summary: Throttle authentication attempts with optional tarpit
...
Introduction
============
This module lets you put a per-IP limit on the number of failed
authentication attempts.
It features an optioanal
[tarpit](https://en.wikipedia.org/wiki/Tarpit_%28networking%29), i.e.
waiting some time before returning an "authentication failed" response.
Configuration
=============
``` {.lua}
modules_enabled = {
-- your other modules
"limit_auth";
}
limit_auth_period = 30 -- over 30 seconds
limit_auth_max = 5 -- tolerate no more than 5 failed attempts
-- Will only work with Prosody trunk:
limit_auth_tarpit_delay = 10 -- delay answer this long
```
Compatibility
=============
Requires 0.9 or later. The tarpit feature requires Prosody trunk.