You can configure your network to contain multiple tiers
of on demand routers (ODRs). In multi-tiered configurations, you
must configure the ODRs in one tier independently from the ODRs in
the other tiers, because the ODRSESSIONIDs of two different tiers
must not be the same.
About this task
An example environment for configuring cell affinity might
include a cluster of ODRs that distribute load to multiple IBM Portal
application servers at the front-end of the network, while at the
back-end there are clusters of ODRs that distribute load to multiple
Web content managers.
There are three important configuration
requirements for this task:
- Within a given tier, any generic server cluster configurations
you create for cell affinity must refer only to ODRs within that tier.
- Within a given tier, the ODR session identifier cookie name, which
is named ODRSESSIONID by default, must be unique for all the other
tiers. You must configure this cookie name as a custom property on
each ODR within that tier, as described in the procedure in this topic.
- If you are using the highly available (HA) plugin configuration
generator, each plugin-cfg.xml configuration must define the ODR session
identifier cookie name to use the IBM HTTP Server to configure ODR
affinity. To define the ODR session identifier cookie name, define
an additional cell-wide custom property associated with the plugin-cfg.xml
generation configuration: ODCPluginCfgOdrSessionIdCookie_<configname>=<CookieName>.
For more information on configuring the HA plug-in configuration generator,
see the Configuring an on demand router to dynamically update the Web server plug-in configuration topic.
Procedure
- From the administrative console, select Servers > On
Demand Routers > <odr_name>.
- Expand On Demand Router Properties.
- Click On Demand Router Settings > Custom Properties
> New.
- Type odrSessionIdCookieName for the name value.
- Type the new cookie name. For example, ODRSID_TIER1.
- Repeat steps 3 through 5 for every ODR within the tier.