Traffic Manager cache bypass

[ops_mdm]

Hi,

I've cache enabled on my Virtual Server that works fine and I have a particular html page in the cache. If a client arrives from a particular IP or Cookie, I want to bypass the cache to go directly to the backend pool (I don't want to disable cache).

Is it possible ? If yes, how to do that ?

Regards.

[Baptiste Assmann]

Hi ops_mdm,

Maybe the following TS could do the trick:

$remote_ip = request.getremoteip();
if (http.cache.exists() && string.IPMaskMatch( $remote_ip, "10.0.0.0/16" )) {
  pool.use(...)
}

Baptiste

[ops_mdm]

Hi Baptiste,

It doesn't works. pool.use or pool.select don't stop the rules processing and cache access (apparently).

Regards.

[PaulWallace · Accepted solution]

Hello, there are a few articles on the community about cache management, I have reposted them here for information:

http://community.brocade.com/t5/vADC-Docs/Feature-Brief-Stingray-Content-Caching/ta-p/73625

http://community.brocade.com/t5/vADC-Blog/Content-caching-for-dynamic-web-applications-with-Stingray...

Of course, yoiu could attempt to enable/disable the cache each time but that might impact other users. 

One method you could use to force a page to bypass the cache would be to add a "no-cache" header to the current request; note that this would bypass the cache, send the request to the servers, and would update the cache on the response:

If (condition) {
   http.addHeader( "Cache-Control", "no-cache" );
}

Alternatively, you could create a "non-cached" virtual server: Create a new virtual server which responds to the non-cached version, say, "nocache.mydomain.com" and include any processing rules you want in the non-cached version. Then in the original virtual server, trap the special requests and redirect to the new service. 

If (condition) {
   http.redirect( "http://nocache.mydomain.com" );
}

http.redirect() issues a response code 302 to redirect to the non-cached service, which then bypass the cache in the main service, and give complete control over what happens in the non-cached service.