Specifications

Chapter 5: Configuring Equalizer Operation
54 Equalizer Installation and Administration Guide
If you change the stale timeout setting while partially established connections are currently in the
queue, those connections will be affected by the new setting.
To set the stale connection timeout, follow these steps:
1. Log into the Equalizer Administration Interface in Edit mode.
2. Select Equalizer > Global Configuration from the Equalizer menu in the main menu bar. The
modify system parameters screen appears in the right frame (see Figure 22 on page 43).
3. Enter a value, in seconds, for stale timeout (default is 15 seconds).
4. Click the commit button.
Enabling Sticky Network Aggregation
Sticky network aggregation enables Equalizer to correctly handle sticky connections from ISPs that
use multiple proxy servers to direct user connections. When you enable sticky network aggregation,
all the connections coming from a particular network are directed to the same server. (Typically, all
the servers in a proxy farm are on the same network.)
When you enable sticky network aggregation, Equalizer routes all the connections from a particular
network to the same server. The netmask value indicates which portion of the address Equalizer
should use to identify particular networks. The mask corresponds to the number of bits in the
network portion of the address:
• 8 bits corresponds to a Class A network
• 16 bits corresponds to a Class B network
• 24 bits corresponds to a Class C network
In previous versions of Equalizer, enabling sticky network aggregation was the equivalent of setting
the sticky network aggregation mask to 24 bits (that is, Equalizer routed all connections from the
same class C network to the same server).
Sticky network aggregation is applicable only for Layer 4 TCP and UDP clusters. For Layer 4
clusters with the spoof flag disabled and for Layer 4 clusters configured for FTP, a sticky record is
maintained for each connection whether sticky network aggregation is enabled or not.
To enable sticky network aggregation, follow these steps:
1. Log into the Equalizer Administration Interface in Edit mode.
2. Select Equalizer > Global Configuration from the Equalizer menu in the main menu bar. The
modify system parameters screen appears in the right frame (see Figure 22 on page 43).
Note – Reducing the stale connection timeout can be an effective way to counter the effects of
SYN flood attacks on server resources. A stale connection timeout of 10 seconds would be an
appropriate value for a site under SYN flood attack.
Note – A potential drawback of using sticky network aggregation is that all users connecting
through a particular proxy farm might be directed to the same server. In practice, this has not
been a problem. Equalizer’s load-balancing algorithms direct other visitors to different servers to
keep the load balanced.