Technical data

70 ServerIron ADX Advanced Server Load Balancing Guide
53-1002435-03
Content-aware cache switching
2
FIGURE 19 Content-aware cache switching
The first time a client requests a URL that ends with "gif" (for example, /home/main/banner.gif) the
following events take place.
1. Because the URL ends with "gif", the CSW policy on the ServerIron ADX directs the request to
one of the cache servers in Server Group ID=1.
2. When a server group consists of more than one cache server, the ServerIron ADX uses a
hashing algorithm to select one of the cache servers, and directs the request to the selected
cache server.
3. Because this is the first time the content is requested, the selected cache server does not have
the content stored, so the cache server retrieves it from the Internet.
4. The cache server receives the content, caches it, and sends it to the requesting client.
The next time a client requests the content, the following events take place.
Internet
CacheServer1
192.168.1.101
SI
RAS
BAR
CacheServer2
192.168.1.102
CacheServer3
192.168.1.103
Server Group ID=1
Cache Group 1
Server Group ID=2
Client requests for URLs that end with gif
are directed to one of the cache servers
in this server group
Client requests for all other URLs
are directed to the cache server in
this server group
Web Queries