https - hopefully not too stupid a question

Chris Edwards chris-ukcrypto at
Mon Jun 18 14:17:52 BST 2012

On Sun, 17 Jun 2012, Florian Weimer wrote:

> * Peter Fairbrother:
> > With the introduction of IPv6 any pressure to share IPs will most
> > likely go away, and I suspect SNI will never really get used in anger.
> IPv6 does not mean that the network will provision multiple addresses
> to you.  You will still have to pay extra for that.

Yep.  Web hosts exist who serve vast numbers of cleartext http websites 
from a single server with a single IP address.  SNI faciliates the same 
thing for https.  

If as a web host you don't want to do SNI, then AIUI you need to assign 
each website an IP address, and configure all the IP addresses as 
"interface aliases" on the server.

I think in the past Linux had a limit of 256, which would be nowhere near 
enough for pile-em-high cheapo webhosting outfits.  So having limitless v6 
addresses isn't going to help, if you can't easily use them this way.

Suspect newer kernels can handle more than 256, but it still may not be 
very suitable for commodity web hosting where everything is driven from a 

But I could be way out of date...

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