Migration from Squid

[Max Clark]

Hello,

I have been looking at Varnish as a replacement to our Squid
infrastructure for a little while now. I am very impressed with the
application and interested in implemented Varnish as a test for some
of our infrastructure. Reading through the wiki there are three things
that I have not figured out how to do / or if it's even possible which
I've detailed below.

1. Cache Peer
  - There are two use cases for the cache peer for our sites. The
first is the proxy only cache peer where the system will check another
proxy for an object and retrieve that object from cache vs. requesting
it from the origin server. This has proven to be extremely effective
at reducing the overall disk footprint of our caches while maintaining
a low hit rate on the origin server. The second of course is querying
the cache on another proxy, fetching and then caching on the local
box.

2. Redirect / Rewrite
  - Obviously running a redirector / rewrite application via a perl
script isn't ideal for performance but has been proven to be an
amazing resource when migrating CMS platforms or to work around
"features" of a specific application platform.

3. Header Replace
  - By default Squid enforces cache policy based on headers served
from the origin system. In some cases we need to then change those
headers when returning data to the client browser. An example would be
to modify the cache-control and expires headers to instruct the
browser not to cache. For a given site we could be setting this as a
global value, for specific URL patterns / directories, or for file
extensions.

Does Varnish support this currently? If not is it on the roadmap?

Thanks,
Max