HP e-Commerce / XML director server appliance sa8250 - Users Guide

C H A P T E R 4 Policy Manager Screen

Sticky Mode

The SA8250 is configured to maintain a session’s state so that serial

requests from a single client are allocated to the same server. This is

called a "sticky" port. This setting may be disabled, based on Source

IP, or based on a Cookie:

Source IP: Source IP sticky mode uses the client’s source IP address

to identify a series of requests to be directed to a single server.

Note: If using SSL services, the SSL session ID maintains a sticky

relationship when Source IP sticky is selected.

Cookie: In cases where requests come through a proxy server, all

requests display to originate from that server’s IP address, thus IP

address is of no use in identifying individual requestors. Cookie sticky

mode provides an active method of identifying requestors in such

situations. When Cookie sticky mode is enabled, a cookie is given to

requesting browsers. Subsequent requests from clients who have

received cookies contain identifying information allowing the SA8250

to direct them to a single server. Cookie mode is available only for

RICH_HTTP.

Sticky Timeout

The current software version for the SA8250 treats the timeout

differently for cookie versus Source IP sticky. With Source IP sticky,

the timeout is reset with every connection from the client (so that the

timeout is effectively an "idle time"). With cookie sticky, the timeout

starts with the first connection from the client to the server, and never

gets reset. When the cookie expires, even if actively being used, the

next connection will be load balanced to a new server.

Workaround: We recommend that you set the cookie sticky timeout

value to at least 1.5 times the maximum amount of time a user will

expect to be stuck to a server. The default is 90 seconds.

Protocol

This read-only field displays the protocol of the Service (TCP).

Status

This read-only field displays the status of the selected Service

("Active" or "Inactive").

Control or Display Description

Additional Service Tab Controls and Displays (continued)