Enable load balancing virtual servers to redirect requests to cache
If a load balancing virtual server is configured to listen on a particular IP address and port combination, it takes precedence over the cache redirection virtual server for any requests destined for that address-port combination. Therefore, the cache redirection virtual server does not process those requests.
If you want to override this functionality and let the cache redirection virtual server decide whether the request should be served from the cache or not, configure the particular load balancing virtual server to be cacheable.
Such a configuration is typically used when an ISP uses a NetScaler appliance at the edge of its network and all traffic flows through the appliance.
Enable load balancing virtual servers to redirect requests to the cache by using the CLI
At the command prompt, type:
- set lb vserver <name> [-cacheable ( YES | NO)] - show lb vserver [<name>]
set lb vserver Vserver-LB-CR –cacheable YES > show lb vserver vserver-LB-CR Vserver-LB-CR (10.102.20.30:80) - HTTP Type: ADDRESS State: DOWN Last state change was at Fri Jul 2 08:47:52 2010 Time since last state change: 0 days, 01:05:51.510 Effective State: DOWN Client Idle Timeout: 180 sec Down state flush: ENABLED Disable Primary Vserver On Down : DISABLED Port Rewrite : DISABLED No. of Bound Services : 1 (Total) 0 (Active) Configured Method: LEASTCONNECTION Mode: IP Persistence: NONE Cacheable: YES PQ: OFF SC: OFF Vserver IP and Port insertion: OFF Push: DISABLED Push VServer: Push Multi Clients: NO Push Label Rule: none 1) Service-HTTP-1 (10.102.29.40: 80) - HTTP State: DOWN Weight: 1 Done
For transparent cache redirection, the appliance intercepts all traffic and evaluates every request to determine whether it is cacheable. Non-cacheable requests are sent unchanged to the origin server.
When using transparent cache redirection, you may want to turn off cache redirection for load balancing virtual servers that always direct traffic to origin servers.
Turn off caching for a load balancing virtual server by using the CLI
To turn off caching for a load balancing virtual, use the unset lb vserver command instead of set lb vserver. Specify a value of NO value for the cacheable parameter.
Enable or disable load balancing virtual servers to redirect requests to the cache by using the GUI
- Navigate to Traffic Management > Load Balancing > Virtual Servers.
- In the details pane, select the virtual server from which you want to enable/disable the caching, and then click Open.
- On the Advanced tab, select/clear Cache Redirection check box.
- Click OK.