I think I have same kind of problems with Fedora. I am using Linux as a proxy server with Squid and about a year ago upgraded from Fedora5 to Fedora6. After that we started to have mysterious problems with some websites (e.g. http://www.enterprise.com)
. I found also some website were slower than expected (ftp://ftp.funet.fi/pub/mirrors/fedor...dora/i386/iso/
downloding 40 kBytes/s instead of 200 kbytes/s which is the speed or our inet connection)
Same sites worked ok (from Windows) when bypassing proxy. Then I found that the same slowness applies when I use lynx or ftp locally in Linux. I have tried to change nics or with a different pc. Changing MTU or speed&duplex or different switch&cabling or trying bonding didn't help either. Same pc & nic works with Fedora5. Tried another pc which has still Fedora4 and it worked. Speed is slow with Fedora7, Fedora6 and Centos5. Haven't tried other distributions.
And no, the reason is not in the dns, because connection is fast and first two seconds downloading is fast. Speed get slower only after that.
My proxy works now ok in an old workstation with Fedora5, but would like to solve this. My internet connection is 2 Mbits/s and NATted in our firewall.