On Sun, 8 Aug 2010, Yasuhiro Araki wrote:
I suggest cdn uses the addresses given by the mirror administrators, at least for those in the official mirror list. It's probably the safest method.Right. However, it requires collaboration with each mirror administrators. Current cdn.debian.net uses debian mirrors without collaboration. If "ftp.br.debian.org" apache server uses mod_rewrite to process "http://200.17.202.1/debian"; -> "http://ftp.br.debian.org/debian/";, current cdn.debian.net can use it.
I don't see what the issue is.As I understand it, cdn.debian.net is a DNS-based cdn, meaning that it returns different A records based on the GeoIP or IP address of the DNS resolver. So, in the example of a query from a location served by brazilian mirrors, it *cannot* return a hostname such as a redirect to http://ftp.br.debian.org. Instead, it would return a list of A records including 200.17.202.1, and the client would connect to 200.17.202.1 to make the request.
If the original request was ftp, it would be making an ftp request - something like ftp://200.17.202.1/debian/... and there would be no problem. If the original request was http, it would be connecting to 200.17.202.1 and making a http request something like http://cdn.debian.net/debian/... which would not return the debian repository unless that is the default name-based virtual host, or there is a name-based virtual host definition for cdn.debian.net.
Carlos says it doesn't make sense to make debian the default name based vhost as there are many other mirrors hosted on the same IP address. Why not make cdn.debian.net a virtualhost alias (eg. apache's ServerAlias directive) for ftp.br.debian.org? And before any host can be placed within the cdn, availability should be checked whether it responds to the cdn.debian.net name, using something like the following and replacing the target IP address:
curl -H "Host: cdn.debian.net" http://200.17.202.1/debian/project/trace/ftp-master.debian.orgAs I said, I don't see what the issue is. If there is an issue, can anyone explain it?