doc

Signed-off-by: Abhishek Choudhary <shreemaan.abhishek@gmail.com>

Author: shreemaan-abhishek

docs/en/latest/plugins/limit-conn.md

@@ -44,6 +44,7 @@ The `limit-conn` Plugin limits the rate of requests by the number of concurrent
 | only_use_default_delay   | boolean | False    | false       |      | If false, delay requests proportionally based on how much they exceed the `conn` limit. The delay grows larger as congestion increases. For instance, with `conn` being `5`, `burst` being `3`, and `default_conn_delay` being `1`, 6 concurrent requests would result in a 1-second delay, 7 requests a 2-second delay, 8 requests a 3-second delay, and so on, until the total limit of `conn + burst` is reached, beyond which requests are rejected. If true, use `default_conn_delay` to delay all excessive requests within the `burst` range. Requests beyond `conn + burst` are rejected immediately. For instance, with `conn` being `5`, `burst` being `3`, and `default_conn_delay` being `1`, 6, 7, or 8 concurrent requests are all delayed by exactly 1 second each. |
 | key_type        | string  | False      | var   | ["var","var_combination"] | The type of key. If the `key_type` is `var`, the `key` is interpreted a variable. If the `key_type` is `var_combination`, the `key` is interpreted as a combination of variables.    |
 | key       | string  | False      | remote_addr |   | The key to count requests by. If the `key_type` is `var`, the `key` is interpreted a variable. The variable does not need to be prefixed by a dollar sign (`$`). If the `key_type` is `var_combination`, the `key` is interpreted as a combination of variables. All variables should be prefixed by dollar signs (`$`). For example, to configure the `key` to use a combination of two request headers `custom-a` and `custom-b`, the `key` should be configured as `$http_custom_a $http_custom_b`. |
+| key_ttl   | integer | False      | 60          |   | The TTL of the Redis key in seconds. Used when `policy` is `redis` or `redis-cluster`. |
 | rejected_code   | integer | False      | 503   | [200,...,599]   | The HTTP status code returned when a request is rejected for exceeding the threshold.     |
 | rejected_msg    | string  | False        |       | non-empty   | The response body returned when a request is rejected for exceeding the threshold.     |
 | allow_degradation       | boolean | False      | false   |   | If true, allow APISIX to continue handling requests without the Plugin when the Plugin or its dependencies become unavailable.        |