Difference between revisions of "Static Routes IPv6 Cisco IOS"

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=Next Hop address=
 
=Next Hop address=
When configuring static Routes in IPv6 it is not recommended to use [[Global Unicast IPv6 Address|global unicast]] addresses as next-hop address. Use [[Link-Local IPv6 Address|Link Local]] adresses.
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When configuring static Routes in IPv6 it is not recommended to use [[Global Unicast IPv6 Address|global unicast]] addresses as next-hop address. Use the [[Link-Local IPv6 Address|Link Local]] adresses.
  
 
{{Technote|heading=extract from {{rfc|rfc=2461}}
 
{{Technote|heading=extract from {{rfc|rfc=2461}}
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}}
 
}}
 
[[Link-Local IPv6 Address|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 IPv6 Address|Link Local]] address.
 
[[Link-Local IPv6 Address|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 IPv6 Address|Link Local]] address.
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=Random Link-local=
 
=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|Link Local]] IPv6 address to match the  [[Global Unicast IPv6 Address|global unicast]] address. See example below.
 
How to avoid this mess I do not know. When configuring IPv6 addresses on Router interfaces I set the [[Link-Local IPv6 Address|Link Local]] IPv6 address to match the  [[Global Unicast IPv6 Address|global unicast]] address. See example below.
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</source>
 
</source>
 
==Prefix Renumbering==
 
==Prefix Renumbering==
The above method gives the problem when a site i 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.
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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.
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==Default Gateway==
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If the Router is Default Gateway it's preferable to set the Router Preference to high
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<source lang=cli>
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interface FastEthernet1/0
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ipv6 nd router-preference High
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</source>
  
 
=Links=
 
=Links=

Latest revision as of 17:50, 18 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 the Link Local adresses.

Clean.png
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-local

Prefix 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

Links