Artifactory is designed to cache on demand, not to mirror all of the content. Besides the fact that if it were all mirrored to the local Artifactory, only 20% of those files would ever be used, most remote sites will block users trying to do this due to the bandwidth cost. What is the use case for such a thing?
Use case is very simple and IMHO very common:
For production I need slice of repository. Any new package update of package should be checked on staging. it is not possible to have 2 production hosts with different set of packages.
For now i have workaround: small script for create file tree and then HEAD request to each file, then switch repo offline by API request.
But it would be great to have that feature as part of artifactory.