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Cisco Catalyst Blade Switch 3130 for Dell Software Configuration Guide
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Chapter39 Configuring IPv6 Unicast Routing Understanding IPv6
Note IPv6 packets are routed in hardware across the stack provided the packet does not have
exceptions (IPv6Options) and the switches in the stack have not run ou t of h ardwa re
resources.
–
flushes the CEFv6 tables on master re-election
With IPv4 unicast routing, if the stack detects that the stack master is down and elects one of the stack
members to be the new stack master, except for a momentary interruption, the hardware continues to
forward packets with no protocols active. With IPv6, the switch does not continue forwarding packets.
On election of a new stack master, the stack might need up to 60 seconds to recover all rout es and resume
forwarding traffic.
IPv6 host functionality is supported on the stack master, and all IPv 6 ap pl icat ions run on the s ta ck
master.
SDM Templates
To allocate system resources for unicast routes, MAC addresses, ACLs and other features, the switch
SDM templates prioritize system resources to optimize support for certain features. You select the
template that best suits the switch environment by entering the sdm prefer global configuration
command. For more information about SDM templates, see Chapter8, “Configuring SDM Templates.”
You can select SDM templates to support IP Version 6 (IPv6). The dual IPv4 and IPv6 templates allow
the switch to be used in dual stack environments (supporting both IPv4 and IPv6).
Note If you try to configure IPv6 without first selecting a dual IPv4 and IPv6 template, a warning message is
generated.
•In IPv4-only environments, the switch routes IPv4 packets and applie s IP v4 QoS and ACLs in
hardware. IPv6 packets are not supported.
•In dual IPv4 and IPv6 environments, the switch routes both IPv4 and IPv6 packets and ap plies IPv4
security and QoS ACLs. The switch also routes IPv6 security ACLs in hardware.
Note Using the dual stack templates results in less hardware memory capacity allowed for each resource, so
do not use if you plan to forward only IPv4 traffic.

Dual IPv4-and IPv6 SDM Templates

These SDM templates support IPv4 and IPv6 environments:
Note This release does not support IPv6 multicast routing or QoS. This release does support IPv6 Multicast
Listener Discovery (MLD) snooping.
•Dual IPv4 and IPv6 default template—supports Layer 2, multicast, routing, QoS, and ACLs for
IPv4; and Layer 2, routing, and ACLs for IPv6 on the switch.
•Dual IPv4 and IPv6 routing template—supports Layer 2, multicast, routing (includi ng policy-based
routing), QoS, and ACLs for IPv4; and Layer 2, routing, and ACLs for IPv6 on the swi tc h.