On a system with accidentally no DNS configured: # emerge-webrsync [...] Fetching most recent snapshot ... Trying to retrieve 20170227 snapshot from http://distfiles.gentoo.org ... Fetching file portage-20170227.tar.xz.md5sum ... Fetching file portage-20170227.tar.bz2.md5sum ... Fetching file portage-20170227.tar.gz.md5sum ... 20170227 snapshot was not found [...] The only indication that something went wrong is a generic "not found", which doesn't distinguish between no network, not reachable, actually not on server and other potential errors. This makes debugging more difficult ...