Difference between revisions of "Static Routes IPv6 Cisco IOS"
m (→Prefix Renumbering) |
m (→Random Link-local) |
||
| Line 20: | Line 20: | ||
==Prefix Renumbering== | ==Prefix Renumbering== | ||
The above method gives the problem when a site is renummbered having multiple IPv6 [[Global Unicast IPv6 Address|global unicast]] addresses for a period. There can be only one [[Link-Local IPv6 Address|Link Local]] IPv6 Address pr. Interface. | The above method gives the problem when a site is renummbered having multiple IPv6 [[Global Unicast IPv6 Address|global unicast]] addresses for a period. There can be only one [[Link-Local IPv6 Address|Link Local]] IPv6 Address pr. Interface. | ||
| + | ==Default Gateway== | ||
| + | If the Router is Default Gateway it's preferable to set the Router Preference to high | ||
| + | <source lang=cli> | ||
| + | interface FastEthernet1/0 | ||
| + | ipv6 nd router-preference High | ||
| + | </source> | ||
=Links= | =Links= | ||
Revision as of 16:12, 17 December 2011
The basic syntax for configuring IPv6 statis routes is the same as in IPv4
- IPv4
- ip route [ipv4_prefix][ipv4_address_mask][ipv4_if_address]
- IPv6
- ipv6 route [ipv6_prefix/prefix_length][ipv6_if_address]
- Ex: ipv6 route ::/0 FastEthernet0/1 FE80::206:2AFF:FEa0:ce84
Next Hop address
When configuring static Routes in IPv6 it is not recommended to use global unicast addresses as next-hop address. Use Link Local adresses.
 |
A router must be able to determine the Link Local address of each of its neighboring routers in order to ensure that the target address of a Redirect message identifies the neighbor router by its Link Local address. |
| extract from rfc2461 |
Link Local addresses however uses EUI-64 based on the Routers MAC-address. If the Router is replaced the neighboring Routers will have to be reconfigured with the new Link Local address.
Random Link-local
How to avoid this mess I do not know. When configuring IPv6 addresses on Router interfaces I set the Link Local IPv6 address to match the global unicast address. See example below.
interface FastEthernet1/0
ipv6 address 2001:16D8:DD85:B280::2/64
ipv6 address FE80:16D8:DD85:B280::2 link-localPrefix Renumbering
The above method gives the problem when a site is renummbered having multiple IPv6 global unicast addresses for a period. There can be only one Link Local IPv6 Address pr. Interface.
Default Gateway
If the Router is Default Gateway it's preferable to set the Router Preference to high
interface FastEthernet1/0
ipv6 nd router-preference High