Chapter 11: Intrusion Detection and Prevention
182
WatchGuard Firebox System
protection feature will self-activate. Once active, further
connection attempts from the external side of the Firebox
must be verified before being allowed to reach your serv-
ers. Connections that cannot be verified are not allowed
through, thus protecting your server from having a full
backlog.
The SYN Flood protection feature will self-deactivate when
it senses the attack is over.
From Policy Manager:
1
On the toolbar, click the Default Packet Handling icon.
You can also, from Policy Manager, select Setup
=>
Intrusion
Prevention
=>
Default Packet Handling.
The Default Packet Handling dialog box appears.
2
Select the checkbox marked
Block SYN Flood Attacks
.
Changing SYN flood settings
Active SYN flood defenses can occasionally prevent legiti-
mate connection attempts from being completed. If you
find that too many legitimate connection attempts fail
when your SYN flood defense is active, you can change
SYN flood settings to minimize this problem.
You can set the maximum number of incomplete TCP con-
nections the Firebox allows before the SYN flood defense is
activated. The default setting of 60 means that when the
number of TCP connections waiting to be validated climbs
to 61 or above, SYN flood defense is activated. Conversely,
when the number of connections waiting for validation
drops to 59 or less, SYN flood defense is deactivated. You
might need to adjust this setting to custom-fit the SYN
Flood
protection feature for your network. Every time the fea-
ture self-activates, a log message will be recorded stating
SYN Validation: activated
. When the feature self-
deactivates, the log message
SYN Validation: deacti-
vated
will be recorded. If these messages occur frequently
when your server is not under attack, the Maximum
Incomplete Connections setting may be too low. If the SYN
Flood protection feature is not preventing attacks from
Summary of Contents for Firebox X10E
Page 1: ...WatchGuard Firebox System User Guide WatchGuard Firebox System ...
Page 12: ...xii WatchGuard Firebox System ...
Page 44: ...Chapter 2 Service and Support 22 WatchGuard Firebox System ...
Page 61: ...Cabling the Firebox User Guide 39 ...
Page 68: ...Chapter 3 Getting Started 46 WatchGuard Firebox System ...
Page 78: ...Chapter 4 Firebox Basics 56 WatchGuard Firebox System ...
Page 156: ...Chapter 8 Configuring Filtered Services 134 WatchGuard Firebox System ...
Page 182: ...Chapter 9 Configuring Proxied Services 160 WatchGuard Firebox System ...
Page 220: ...Chapter 11 Intrusion Detection and Prevention 198 WatchGuard Firebox System ...
Page 242: ...Chapter 12 Setting Up Logging and Notification 220 WatchGuard Firebox System ...
Page 256: ...Chapter 13 Reviewing and Working with Log Files 234 WatchGuard Firebox System ...
Page 274: ...Chapter 14 Generating Reports of Network Activity 252 WatchGuard Firebox System ...