Change from Oracle WC to Varnish

[Poul-Henning Kamp]

In message <201003091353.07106.harri.paivaniemi at tieto.com>, =?iso-8859-1?q?H=2EP
=E4iv=E4niemi?= writes:

>- multiple ip-based virtual hosts (about 50)
>- multiple origin server pools of course
>- origin server polling to see if they are ok
>- both common and site-specific cache-rules
>- different kind of expiration policies

So far no problems.

>- cookie-based and header-based personalization to cache multiple versions of some sites

Varnish allows you to define what goes into the hash-key, and supports
"Vary:" headers, so I think is covered.

Our VCL syntax for dealing with cookies needs to be improved, which
will happen Real Soon Now.

>- origin server capacity throttling / limiting etc

Right now we only have a limit for maximum number of connections.

>- caching both GET, Get with query strings and POST

GET with or without query strings is supported.

POST can be done, provided the message-body can be ignored.

>- have to have some kind of method to order caches to expire (clear)
> specific content immediately when asked

Got that.

>So how is it - can Varnish be used or are we gonna have major
>problems or limitations?

I certainly think Varnish can be used.

Seriously consider doing a gradual phaseover, where you let Varnish
take more and more load from the Oracle WebCache machines.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
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