Proxies are a constant foe of potential Yocto users. We should add a sanity check to verify that core fetch commands which rely on the various proxied traffic (http/https/ftp/etc) can be run. This will potentially be a lengthy test so should use the check_sanity_tmpdir_change() sanity check harness.
In addition to proxies, we also need to check for port blocking firewalls which can block all but http traffic, for example.
Duplicate of #933, closing this one and moving comments there. *** This bug has been marked as a duplicate of bug 933 ***
We can close this bug now that #933 is up to date with details.