Fortinet 359 FortiWeb 5.0 Patch 6 Administration Guide
Action Select which action the FortiWeb appliance will take when it
detects a violation of the rule:
Alert — Accept the request and generate an alert email and/or
log message.
Alert & Deny — Block the request (or reset the connection) and
generate an alert email and/or log message.
You can customize the web page that will be returned to the
client with the HTTP status code. See “Uploading a custom
error page” on page 467 or Error Message.
Period Block — Block subsequent requests from the client for
a number of seconds. Also configure Block Period.
Tip: For improved performance during a confirmed DDoS,
select this option. Attackers participating in the DoS will then be
blocked at the IP layer, conserving FortiWeb resources that
would otherwise be consumed by scanning each attacker’s
request at the HTTP layer, compounding the effects of the
DDoS.
Note: If FortiWeb is deployed behind a NAT load balancer, when
using this option, you must also define an X-header that
indicates the original client’s IP (see “Defining your proxies,
clients, & X-headers” on page 266). Failure to do so may cause
FortiWeb to block all connections when it detects a violation of
this type.
The default value is Alert.
Caution: This setting will be ignored if Monitor Mode is enabled.
Note: Because the new active appliance does not know previous
session history, after an HA failover, for existing sessions, FortiWeb
will not be able to enforce actions for this feature. See “Sessions &
FortiWeb HA” on page 39.
Note: Logging and/or alert email will occur only if enabled and
configured. See “Logging” on page 542 and “Alert email” on
page 576.
Note: If you will use this rule set with auto-learning, you should
select Alert. If Action is Alert & Deny, or any other option that
causes the FortiWeb appliance to terminate or modify the request
or reply when it detects an attack attempt, the interruption will
cause incomplete session information for auto-learning.
Block Period Type the number of seconds that you want to block subsequent
requests from the client after the FortiWeb appliance detects that
the client has violated the rule.
This setting is available only if Action is set to Period Block. The
valid range is from 1 to 10,000 (2.78 hours). The default value is 0.
See also “Monitoring currently blocked IPs” on page 606.
Setting name Description