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I was looking for configuring Slackware to use ipv6 but all instruction I found speak about using an ipv6 tunnel that encapsulate ipv6 request into ipv4 packet and send them to an external router that extracts ipv6 request and sends a reply (or, at least, this is what I understood).

Is that necessary? Isn't there a way to configure a pure ipv6 system? If yes, could you please point me to a guide that clearly explain how to enable ipv6 without this trick?

I would like to configure my Slackware desktop at first, and then do the same with my Centos server.

EDIT: maybe I gave you too few information. Sorry. I'll write some more information thanks to the posted guide.

~$ test -f /proc/net/if_inet6 && echo "Running kernel is IPv6 ready"
Running kernel is IPv6 ready

So, it seems ipv6 is enabled in my kernel.

Some other output from ifconfig, route and /etc/resolv.conf content (with opendns):

~$ /sbin/ifconfig wlan0 | grep inet6
inet6 addr: fe80::21f:3bff:fe60:cc5b/64 Scope:Link

~$ /sbin/route -A inet6 | grep wlan0
fe80::/64                      ::                         U    256 0     0 wlan0
ff00::/8                       ::                         U    256 0     0 wlan0

~$ cat /etc/resolv.conf
nameserver 2620:0:ccc::2

But still, with ping6 I can only ping localhost (::1). Everything else is unreachable. Normal ping works fine.

That is why I was asking if I am obliged to use a tunnel.

share|improve this question
Do you have IPv6 connectivity to the internet/do you want to have only local IPv6 traffic? – Tibor Jun 29 '12 at 7:49
If IPV6 is enabled in your kernel and it is setup on the upstream routers that you connect to, then you don't have to do anything. If it isn't working call your ISP. – Zoredache Jun 29 '12 at 8:06
Is there a way to find out if the upstream router supports it? – Zagorax Jun 29 '12 at 8:25
If the upstream router supports it, your nodes will configure themselves with public IPv6 addresses. If they're not, odds are it doesn't. You can check with rdisc6. (Your distribution probably includes it in a package called "ndisc6".) – David Schwartz Jun 29 '12 at 9:14

Just set an IPv6 IP if you have an IPv6 infrastructure. For example using "ip" or "ifconfig":

# /sbin/ip -6 addr add <ipv6address>/<prefixlength> dev <interface> 

# /sbin/ip -6 addr add 2001:0db8:0:f101::1/64 dev eth0 

# /sbin/ifconfig <interface> inet6 add <ipv6address>/<prefixlength>

# /sbin/ifconfig eth0 inet6 add 2001:0db8:0:f101::1/64 

A complete howto can be found at:

share|improve this answer
It's clear from the question there is no IPv6 infrastructure in place, since router discovery doesn't set up IPv6, and the question suggests the author does not know how to disable this. So some cut-and-paste instructions for assigning an address aren't much help in my opinion. It still won't work. – Koos van den Hout Jul 12 '12 at 10:18

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