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Cisco Catalyst Blade Switch 3130 for Dell Software Configuration Guide
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Chapter39 Configuring IPv6 Unicast Routing
Configuring IPv6
To disable IPv6 CEF or distributed CEF, use the no ipv6 cef or no ipv6 cef distributed global
configuration command. To reenable IPv6 CEF or dCEF if it has been disabled, use the ipv6 cef or ipv6
cef distributed global configuration command. You can verify the IPv6 state by entering the show ipv6
cef privileged EXEC command.
Configuring Static Routing for IPv6
Static routes are manually configured and define an explicit route between two networking devices. The
benefits of static routes include security and resource efficiency. Static routes use less bandwidth than
dynamic routing protocols because there is no requirement for routes to be calculat ed and
communicated. The main disadvantage of using static routes is that static routes are not automatically
updated, as with a dynamic routing protocol, and must be manual ly reconfigured if the network topology
changes. Static routes are useful for smaller networks with only one path to an outside network or to
provide security for a larger network for certain types of traffic.
There are types of static routes:
•Directly attached static routes—Only the output interface is specified because the destination is
assumed to be directly attached to this interface. The packet dest ina tion is used as the next hop
address. A directly attached static route is valid only when the specified interface is IPv6-enabled
and is up.
•Recursive static routes—Only the next hop is specified, and the output interface is derived from the
next hop. A recursive static route is valid only when the specified next hop results in a valid IPv6
output interface, the route does not self-recur, and the recursion depth does not exceed the ma ximum
IPv6 forwarding recursion depth.
•Fully specified static routes—Both the output interface and the next hop are specified. The next hop
is assumed to be directly attached to the specified output interface. A fully specified route is valid
when the specified IPv6 interface is IPv6-enabled and up.
•Floating static routes—Any of the three types of static routes can be f loa ting st at ic rou tes , use d t o
back up dynamic routes learned through configured routing prot ocol s. A f loati ng sta tic r ou te is
configured with a less efficient administrative distance than the routing protocol it is backing up.
Therefore, the dynamic route is always used for routing traffic in preference to the floating static
route. If the dynamic route is lost, the floating static route is used in its place.
Note Before configuring a static IPv6 route, you must enable routing by using the ip routing global
configuration command, enable the forwarding of IPv6 packets by using the ipv6 unicast-routing global
configuration command, and enable IPv6 on at least one La yer 3 i nte rface by co nfiguri ng a n IPv6
address on the interface.