ipv6 question

Fri Mar 11 19:15:36 UTC 2011

Hi

Then I won't use this ipv6 address 2001:db8:cafe:1111::12 for test

Acutually, I have one in eth0 when I run ifconfig -a

          inet6 addr: fe80::20c:29ff:fe3c:92a1/64 Scope:Link


but I also can't ping it

ping6 fe80::20c:29ff:fe3c:92a1
connect: Invalid argument


but ping6 ::1 is fine

ping6 ::1
PING ::1(::1) 56 data bytes
64 bytes from ::1: icmp_seq=0 ttl=64 time=7.18 ms
64 bytes from ::1: icmp_seq=1 ttl=64 time=0.050 ms


--- On Wed, 3/9/11, Karl Auer <kauer at biplane.com.au> wrote:

> From: Karl Auer <kauer at biplane.com.au>
> Subject: Re: ipv6 question
> To: nanog at nanog.org
> Received: Wednesday, March 9, 2011, 11:11 PM
> On Thu, 2011-03-10 at 11:43 +1100,
> Mark Andrews wrote:
> > In message <1299711449.2109.98.camel at karl>, Karl
> Auer writes:
> > > On Wed, 2011-03-09 at 09:01 -0600, imNet
> Administrator wrote:
> > > > Where are you pinging it from? also, the
> 2001:db8::/32 prefix is used
> > > > for "documentation purposes" and might be
> handled differently by the
> > > > TCP/IP stack.
> > > 
> > > Works fine in Linux - I've been using it (in an
> isolated training room
> > > setup) for years.
> > > 
> > > Regards, K.
> > 
> > It is not a good idea to use the documentation prefix
> for anything
> > other than documentation.  How hard is it to
> generate a ULA and use
> > it?
> 
> I suppose I took/take the view that it *is*, in a sense,
> being used for
> documentation.
> 
> The network is a training network, isolated from the
> Internet, and used
> for demonstration purposes. It's a good way to engrave the
> doco prefix
> in the students' minds. It also allows all the slides,
> exercises and
> other documentation to use the documentation prefix and yet
> directly
> match the demonstration network.
> 
> ULA prefixes have little internal logic and are hard to
> remember. Not a
> problem in production, but just another barrier in a
> training
> environment. "2001:db8::/32" is very easy to remember (I
> guess that's
> the point) and easy to add easy-to-use subnets into.
> 
> However, I do appreciate that it's a bit of an edge case.
> In my training
> I specifically draw the students' attention to this fact.
> 
> Thanks, K.
> 
> -- 
> ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> Karl Auer (kauer at biplane.com.au) 
>              
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> http://www.biplane.com.au/kauer/     
>          
>    +61-428-957160 (mob)
> 
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