yum and proxy

[Rick Marshall]

I don't know if this has been mentioned and the solution listed, but 
just for the record:

After upgrading from fc4 to fc5 I couldn't get yum to work - and a 
search through the internet revealed lots of other people having the 
same problem, but no solution. Problems getting baseurl etc.

As it turns out I had a problem also using wget which complained about a 
proxy - strange because I wasn't running squid!

Then I found the environment variable http_proxy is being set to the 
localhost. Yum quietly uses this and when it can't find the proxy it 
gives misleading messages (albeit true) about not being able to find a 
baseurl.

Solution: "unset http_proxy" then yum

Question: how and why is this being set if squid or some other proxy 
isn't set up?

Thanks

Rick