Once upon a time, Nathan Ward <na...@daork.net> said: > On 14/10/2009, at 2:14 PM, Chris Adams wrote: > >What about web-hosting type servers? Right now, I've got a group of > >servers in a common IPv4 subnet (maybe a /26), with a /24 or two > >routed > >to each server for hosted sites. What is the IPv6 equivalent? I can > >see a /64 for the common subnet, but what to route for aliased IPs for > >web hosts? It is kind of academic right now, since our hosting > >control > >panel software doesn't handle IPv6, but I certainly won't be putting > >2^64 sites on a single server. Use a /112 here again as well? Use a > >/64 per server because I can? > > Why route them to the servers? I would just put up a /64 for the web > servers and bind addresses to your ethernet interface out of that /64 > as they are used by each site. > I guess you might want to route them to the servers to save ND entries > or something on your router?
In the past, we saw issues with thousands of ARP entries (it has been a while and I don't remember what issues now though). Moving a block from one server to another didn't require clearing an ARP cache (and triggering a couple of thousand new ARP requests). Also, it is an extra layer of misconfiguration-protection: if the IPs are routed, accidentally assigning the wrong IP on the wrong server didn't actually break any existing sites (and yes, that is a lesson from experience). Of course, with IPv4, you never assigned a large enough block to begin with that would anticipate all growth, so routing additional blocks was a lot easier than changing blocks, cleaner than secondary IPs multiplying like crazy, etc., etc. None of that would be an issue with a single /64. -- Chris Adams <cmad...@hiwaay.net> Systems and Network Administrator - HiWAAY Internet Services I don't speak for anybody but myself - that's enough trouble.