To my amazement, Telecom Italia released a pilot project of IPv6 deployment on residential/dynamic ip only adsl internet access, but on theirs support site there’s configuration only for some useless systems. So, I’ve decided to write a configuration for Cisco platform.
Usually the typical Telecom Italia PPPoE or PPPoA ADSL connection with dynamic IPv4 only was authenticated with “aliceadsl” as user and password, now with bran new credential along IPv4 the endpoint router advertise a IPv6 /64 class (always dynamic).
username: adsl@alice6.it
password: IPV6@alice6
And now IOS configuration:
– ATM inteface:
interface ATM0/0/0
no ip address
atm restart timer 300
no atm ilmi-keepalive
dsl operating-mode auto
hold-queue 100 in
!
interface ATM0/0/0.1 point-to-point
pvc 8/35
vbr-nrt 380 380
oam-pvc manage
encapsulation aal5mux ppp dialer
dialer pool-member 1
– Dialer inteface:
interface Dialer0
mtu 1492
ip address negotiated
ip nbar protocol-discovery
ip flow ingress
ip virtual-reassembly
encapsulation ppp
dialer pool 1
dialer-group 1
ipv6 address autoconfig
ipv6 enable
no cdp enable
ppp authentication chap callin
ppp chap hostname adsl@alice6.it
ppp chap password 0 IPV6@alice6
ppp pap sent-username adsl@alice6.it password 0 IPV6@alice6
– Route configuration:
ip route 0.0.0.0 0.0.0.0 Dialer0
ipv6 route 2000::/3 Dialer0
You can check with following command:
route01#sh ip int brief | sec Dialer0
Dialer0 XXX.XXX.XXX.XXX YES IPCP up up
route01#sh ipv6 int brief | sec Dialer0
Dialer0 [up/up]
FE80::1
2A01:2003:xxxx:xxxx::1
You can discover your /64 assigned class with:
route01#sh ipv6 int di0 | sec Global
Global unicast address(es):
2A01:2003:xxxx:xxxx::1, subnet is 2A01:2003:xxxx:xxxx::/64 [PRE]
valid lifetime 2591993 preferred lifetime 604793
route01#
I’ve left out NAT and other further configuration.
Update: prefix delegation
Very good, and is this /64 routable or you have to answer NDPs for the hosts behind the router?
I didn’t answer intentionally.
Yes, is routable but the only way to use /64 on hosts behind the router is with prefix delegation (rfc3769).
Sincerely I don’t like this kind of solution because in this case, the prefix was routed through interface Dialer0, used like point-to-point but without any address, and the ip was physically on other interface (vlan, fastethernet, serial)
I see. Very interesting :)
I’ve made a prefix delegation configuration: http://blog.deepreflect.net/?p=1210
Leo, are you sure it’s a good idea to route 2000::/3? It’s the only part of IPv6 space, but i’m almost sure you’d better route the entire space trough the interface (::/0).
Just as 0.0.0.0/0