Coyote Point Systems Equalizer, Руководство по установке и администрированию

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Chapter 5: Administering Virtual Clusters
70 Equalizer Installation and Administration Guide
Figure 49 Enabling cookie based persistence
4. Select the Enable Persistence checkbox.
5. To have Equalizer insert a persistence cookie in the response even if the server is not
already sending a cookie to the client, select the Always use Cookie checkbox. Unless
this option is selected, Equalizer only inserts a persistence cookie if the server is
already sending some other cookie to the client.
6. Specify the number of seconds before the cookie expires in the Cookie Lifetime field.
If the client submits another request after the cookie expires, the Equalizer will select a
server according to the configured load balancing criteria.
7. To restrict presentation of the cookie to requests where the path component of the
request URI matches a particular path, enter it in the Cookie Path field.
8. To restrict presentation of the cookie to requests directed to servers whose host name is
within the specified domain, enter it in the Cookie Domain field.
Enabling Sticky Connections
Sticky connections are used to maintain persistent sessions for generic TCP and UDP
clusters that do not support L7 load balancing.
The sticky time period is the length of time that Equalizer ensures that new connections from
a particular client are directed to the same server. The timer for the sticky time period
begins to expire as soon as there are no longer any active connections between the client
and the cluster. If a new connection to the cluster is established, the timer for the sticky
time period is reset.
Enabling sticky connections increases the memory and CPU overhead associated with a
connection. The overhead increases as the sticky period increases. You should use the
shortest reasonable period for your application and avoid enabling sticky connections for
applications unless they need it. A reasonable value for the sticky time period for most