Quick trick, adapted from something my boss showed me, on how to clear a cache from behind a proxy.
If you’re using a web browser you can just use CTRL+F5, which I think most people know already. Squid proxies will respect the “no-cache” header, flush the local copy and retrieve a fresh copy from the source.
At the command line this can be done as follows:
Which has the same effect. This is useful when you get a yum error such as:
Which is because the repomd.xml is out of date and refers to a repo db that no longer exists. Therefore you need to flush the proxy cache and yum cache as follows: