Getting yum to work with RHEL / RHN behind a proxy

/etc/sysconfig/rhn/up2date

enableProxy=0

httpProxy=proxyserver.company.com:8080

~/.bash_profile

export http_proxy=http://proxyserver.company.com:8080

export HTTP_PROXY=http://proxyserver.company.com:8080

The thing is, there is no universal agreement among linux command line programs, some seem to use HTTP_PROXY and some use http_proxy.  So, yes, export http_proxy both as lower and UPPER case!

And complicating the picture is that RHN doesn't use either of these -- it pulls the settings out of /etc/sysconfig/rhn/up2date