ZyXEL P-2602HW Betriebsanweisung

Chapter 15 Firewall Configuration

P-2602H(W)(L)-DxA User’s Guide

The following describes the firewall commands. See the Command Interpreter appendix for 
information on the command structure. Each of these commands must be preceded by 

sys 

firewall

 when you use them. For example, type 

sys firewall active yes

 to turn on 

the firewall.

Maximum 

Incomplete High

This is the number of existing half-open 

sessions that causes the firewall to start 

deleting half-open sessions. When the 

number of existing half-open sessions rises 

above this number, the ZyXEL Device 

deletes half-open sessions as required to 

accommodate new connection requests. Do 

not set Maximum Incomplete High to lower 

than the current Maximum Incomplete Low 

number.

100 existing half-open sessions. 

The above values causes the 

ZyXEL Device to start deleting 

half-open sessions when the 

number of existing half-open 

sessions rises above 100, and to 

stop deleting half-open sessions 

with the number of existing half-

open sessions drops below 80.

TCP Maximum 

Incomplete 

This is the number of existing half-open TCP 

sessions with the same destination host IP 

address that causes the firewall to start 

dropping half-open sessions to that same 

destination host IP address. Enter a number 

between 1 and 256. As a general rule, you 

should choose a smaller number for a smaller 

network, a slower system or limited 

bandwidth.

30 existing half-open TCP 

sessions.

Action taken when the TCP Maximum Incomplete reached threshold

Delete the Oldest 

Half Open 

Session when 

New Connection 

Request Comes.

Select this radio button to clear the oldest half 

open session when a new connection request 

comes.

Deny New 

Connection 

Request for

Select this radio button and specify for how 

long the ZyXEL Device should block new 

connection requests when TCP Maximum 

Incomplete is reached. 
Enter the length of blocking time in minutes 

(between 1 and 256).

Apply

Click Apply to save your changes back to the ZyXEL Device.

Cancel

Click Cancel to begin configuring this screen afresh.

Table 83   Firewall: Threshold (continued)

Table 84   Sys Firewall

 Commands

acl

disp

Displays ACLs or a specific ACL set # and rule #.

active

<yes|no>

Active firewall or deactivate firewall
Enables/disables the firewall.

cnt