Subject: Re: IPv6, was IPv10 (fwd)

From: "John R Levine" <[email-masked]>
Date: 29 Dec 2016 14:30:55 -0500

>> I might be able to use ULAs but I have no idea how well ULAs actually work
> 
> Exactly like any other global-scope IPv6 address. They just work. (I speak
> from experience.)

How do I tell my router that the ULAs on the home side of the router are 
different from ULAs on the cableco side?

> If you want static addresses on your servers, it's no different from any 
> other static address. But maybe I am not understanding your concern.

If I knew I had an address range that held still, I would use DHCPv6 and see 
how many of my devices handle it.  What happens if I have ULA addresses handed 
out by DHCPv6 and global addresses from SLAAC?  Do I have to turn off SLAAC?

(If this stuff is all written down somewhere, I would be thrilled to get 
the reference.)

Regards,
John Levine, [email-masked], Taughannock Networks, Trumansburg NY
Please consider the environment before reading this e-mail. https://jl.ly

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From: Brian E Carpenter <[email-masked]>
Date: Fri, 30 Dec 2016 08:54:40 +1300

> different from ULAs on the cableco side?

Your ULAs are all in your ULA /48 prefix. I'm not clear why the cableco would
be using ULAs, but if they do, those address will be in the cableco's ULA /48.
No confusion is possible, and as a border router, it SHOULD drop outbound
packets with source addresses in your ULA /48.

> out by DHCPv6 and global addresses from SLAAC?  Do I have to turn off SLAAC?

In the router advertisements, the prefix information option for the ULA prefix
would need its A flag turned off.

> (If this stuff is all written down somewhere, I would be thrilled to get 

This is more for v6ops or even [email-masked]. To be honest I
don't know if any of the IPv6 books covers this stuff in detail.

    Brian

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From: Mark Andrews <[email-masked]>
Date: Fri, 30 Dec 2016 10:59:42 +1100

> packets with source addresses in your ULA /48.

It should also be dropping incoming traffic from ULAs it is not
configured to pass.  That is the job of a border router.

-- 
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: [email-masked]