At the beginning of the year 2011, we decided to apply the IPv6 configuration to our data center (VeriTeknik) and requested our IPv6 block from RIPE. RIRs give out /32 blocks to LIRs at the first assignment. This article describes basic Cisco IPv6 configuration.
The Preparation Steps
- Request your IPv6 Addresses from your RIR or LIR
- Add IPv6 Route to your AS number in LIR Portal
- Get your IPv6 VLAN IP from your Upstream Provider
- Configure your router
Configuring Cisco Routers for IPv6
Before you start applying IPv6 on your routers make sure that you backup your current configuration.
First of all, make a table of your arguments such as your IP addresses, AS numbers etc like below, we put some values for you to easily analyze the configuration:
|Your AS Number||AS65535|
|Remote As Number||AS1000|
|VLAN IP Your Side (Given by Telco op)||2A01:358:4500:2::2/64|
|VLAN IP remote Side (Telco Side)||2A01:358:4500:2::1|
|Your IPv6 Addresses to Announce||2B00:7300::/32|
Enable IPv6 & IPv6 CEF on your Cisco router:
ipv6 unicast-routing ipv6 cef !
Set your IPv6 address to the interface facing telco:
Don’t delete your IPv4 configuration or other necessary codes, just add
interface GigabitEthernet0/0 description $ETH-WAN$ ipv6 address 2A01:358:4500:2::2/64 ipv6 enable ipv6 virtual-reassembly .. .. !
Switch to BGP configuration by typing “router bgp 65535”
router bgp 65535 . . neighbor 2A01:358:4500:2::1 remote-as 1000 !
type exit and type address-family ipv6 to enter IPv6 configuration
to announce your prefixes type:
address-family ipv6 neighbor 2A01:358:4500:2::1 activate distance bgp 200 200 200 network 2B00:7300::/32 network 2B00:7300:100::/48 redistribute connected redistribute static no synchronization exit-address-family !
Type exit one more and you need to add routes for your IPv6 addresses,
ipv6 route 2B00:7300::/32 Null0 254
This is the basic IPv6 configuration for Cisco routers, now you should be able to communicate with IPv6 enabled hosts. To test your configuration you may assign IPv6 to one of your VLANs, an example given below:
interface GigabitEthernet0/1.201 description LOCAL encapsulation dot1Q 201 . . ipv6 address 2B00:7300:100::1/48 !