Do you need to put your web server on steroids? Do you find it slow and do
not know what to do? If you have the money, I have the solution.

Here is one solution for you. The Big-IP is a all-in-one box where you can do
lots to tweak your web server performance and reliability. Features includes:
- Connection pooling from the Big-IP to your backend web server.
This offloads connection setup time on your web server.
- SSL offloading when you encrypt your web pages. With this feature
you do not need to spend web server CPU cycles to manage SSL sessions.
- RAM cache is also possible which offloads static content that is
downloaded all the time. You can also cache dynamic content if you want.
- Compression of content. Most of the content on a web server is
compressible. With this feature enabled you can save bandwidth, speed up
clients on slow lines and load web pages faster. On a site with much content
you can expect 60-70% reduction in bandwidth requirements using this
feature.
- Load balancing with failover. If your solution needs more than
one web server you can load balance traffic and as soon as a node fails it
will be removed from the pool.
- Web accelerator combines several technologies to try speed up.
- HTTP header manipulation. You can manipulate every http header if
you want.
What you will use depends on your requirements and wallet. Some of the
features above are expensive, but they all work great. You will have to pay
about US$20,000 for the entry level platform.
The Big-IP platform
After one week of work on this platform I have to say that I am impressed. It
is relatively easy to use and configure. All the basic configuration settings
are configured from a web page. Just spend some minutes and read their quick
startup guide to get familiar with their naming conventions.
With less than one hour of configuration you should see improvements on your
solution.
Big-IP customizations
One think I really like is that if I need something that F5 did not think
about I can tweak it myself. Here is the code to cache HTTP 302 replies and
redirect my secure site to HTTPS.
when HTTP_RESPONSE {
if { [HTTP::status] == "302" } {
CACHE::enable
}
}
when HTTP_REQUEST {
if { [HTTP::uri] starts_with "/secure"} {
HTTP::redirect https://mysite/secure
}
}
This is called
iRules.
The language is based on TCL.
RAM cache
Squid is probably the most known cache server in the world. But it is only a
cache. Big-IP is lots and lots of more, but probably not the best cache-only
solution. It only caches to memory, so if you serve big content like images,
videos and so forth and require a big cache this is not the best solution.
But for all other uses it works great in conjunction with compression and
load balancing.
Web Accelerator
This module rewrites the web page so it loads faster and tries not to
transfer redundant data twice to the client. This is at least what F5 says.
Out of the box the web accelerator have profiles for Microsoft Exchange
Server and Sharepoint. (And some others, but I don't remember now.)
On low bandwidth and high latency inline objects (like images, CSS,
javascript) are rewritten to be downloaded from other servers. This to overcome
the limitation in Internet Explorer to only open open two connections to one
server at a time.
Combined with compression this should make some chatty Microsoft web
applications more speedy over the Internet.
Conclusion
I love this product. It have lots of features and you can tweak and tune it
to fit to most web applications. I spent much time evaluating the RAM cache but
see lots of potential in all the other features.
The Big-IP documentation is not impressive. Nor the Wiki on DevCentral. You
need to spend some time to figure out how to use it if you need custom features.
PS! The load balancer feature is not only for web traffic. All kind of
traffic can be load balanced.
Good luck! If you have any questions do not hesitate to ask me!
Labels: F5, review