Prestige 2602HW Series User’s Guide

Whenever the number of half-open sessions with the same destination host address rises above

athreshold (TCP Maximum Incomplete), the Prestige starts deleting half-open sessions according to one of the following methods:

•If the Blocking Time timeout is 0 (the default), then the Prestige deletes the oldest existing half-open session for the host for every new connection request to the host. This ensures that the number of half-open sessions to a given host will never exceed the threshold.

•If the Blocking Time timeout is greater than 0, then the Prestige blocks all new connection requests to the host giving the server time to handle the present connections. The Prestige continues to block all new connection requests until the Blocking Time expires.

The Prestige also sends alerts whenever TCP Maximum Incomplete is exceeded. The global values specified for the threshold and timeout apply to all TCP connections.

Click Firewall, and Threshold to bring up the next screen.

Figure 78 Firewall: Threshold

The following table describes the labels in this screen.

Table 54 Firewall: Threshold

LABEL

DESCRIPTION

DEFAULT VALUES

 

 

 

Denial of Service

 

 

Thresholds

 

 

One Minute Low

This is the rate of new half-open sessions that

80 existing half-open sessions.

 

causes the firewall to stop deleting half-open

 

 

sessions. The Prestige continues to delete

 

 

half-open sessions as necessary, until the

 

 

rate of new connection attempts drops below

 

 

this number.

 

Chapter 14 Firewall Configuration

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