Server IPv6 Addresses?

[Nick Pais]

Hello everyone, I have a quick (I suppose), easy and possibly stupid question: On the tunnelservers (or in HENET's network in general), how do you set up to add all those tunnel "gateways" (For example: Server IPv6 Address:2001:470:1f10:a10::1/64) to the servers? I doubt they are added one by one, instead the server has a /48 allocated to it (or bigger). I've always had this uncertainty and want to have it cleared up for me. Thanks!

[broquea]

Each tunnel has its own interface. So yes, each ::1/64 is configured as the interface is configured, one by one. The /48 is just an allocation pool that the tunnels get their /64s out of.

[Nick Pais]

Each tunnel has its own interface. So yes, each ::1/64 is configured as the interface is configured, one by one. The /48 is just an allocation pool that the tunnels get their /64s out of.

Ah, ok. Thanks for clearing that up for me!

[kasperd]

I'm curious how large chunks of addresses you assign to a tunnel server each time. Since it is possible for users to request a /48, I assume you don't assign that long prefixes to the tunnel servers, as you'd have to allocate a new /48 to the tunnel server each time a user requests a /48.

[antillie]

Just a wild guess but I would imagine that they assign /32's to the tunnel servers as needed. Slice a /32 into 65,536 /48's, cut a few of those up into 65,536 /64's each and you have plenty of /64 and /48 blocks for use on tunnels and as routed blocks on each tunnel server.

[broquea]

2001:470::/32 can only have 1 /32 :)
Although we do have a /24 now, but that will be put to other uses :D
We'll leave this unanswered as to our specifics, but feel free to guess away!

[kasperd]

Although we do have a /24 now, but that will be put to other uses :D

I thought such short prefixes where only handed out temporarily for 6rd deployments and similar transition mechanisms.

We'll leave this unanswered as to our specifics, but feel free to guess away!

A quick traceroute reveals that at least 2001:470:28::/48 which is used for /64s on sto1 is routed only as a /48. Oddly the routed /64s and the tunnel endpoints are from a different /48. The two /48s are adjacent, but could not be aggregated into a /47.

So 2001:470:27::/48 and 2001:470:28::/48 are both routed to the same tunnel server, but 2001:470:26::/48 and 2001:470:29::/48 are elsewhere.

I cannot figure out what the reasoning would have been behind this.

[broquea]

I thought such short prefixes where only handed out temporarily for 6rd deployments and similar transition mechanisms.

Nothing temporary about this allocation :)