Concept Guide

Table Of Contents
The OSPFv3 ipv6 ospf area command enables OSPFv3 on the interface and places the interface in an area. With OSPFv2,
two commands are required to accomplish the same tasks the router ospf command to create the OSPF process, then
the network area command to enable OSPF on an interface.
NOTE: The OSPFv2 network area command enables OSPF on multiple interfaces with the single command. Use the
OSPFv3 ipv6 ospf area command on each interface that runs OSPFv3.
All IPv6 addresses on an interface are included in the OSPFv3 process that is created on the interface.
Enable OSPFv3 for IPv6 by specifying an OSPF process ID and an area in INTERFACE mode. If you have not created an OSPFv3
process, it is created automatically. All IPv6 addresses configured on the interface are included in the specified OSPF process.
NOTE: IPv6 and OSPFv3 do not support Multi-Process OSPF. You can only enable a single OSPFv3 process. To create
multiple OSPF processes you need to have multiple VRFs on a switch.
Set the time interval between when the switch receives a topology change and starts a shortest path first (SPF) calculation.
timers spf delay holdtime
NOTE: To set the interval time between the reception of topology changes and calculation of SPF in milli seconds, use the
timers spf delay holdtime msec command.
Example
DellEMC#conf
DellEMC(conf)#ipv6 router ospf 1
DellEMC(conf-ipv6-router_ospf)#timer spf 2 5 msec
DellEMC(conf-ipv6-router_ospf)#
DellEMC(conf-ipv6-router_ospf)#show config
!
ipv6 router ospf 1
timers spf 2 5 msec
DellEMC(conf-ipv6-router_ospf)#
DellEMC(conf-ipv6-router_ospf)#end
DellEMC#
Enabling IPv6 Unicast Routing
To enable IPv6 unicast routing, use the following command.
Enable IPv6 unicast routing globally.
CONFIGURATION mode
ipv6 unicast routing
Applying cost for OSPFv3
Change in bandwidth directly affects the cost of OSPF routes.
Explicitly specify the cost of sending a packet on an interface.
INTERFACE mode
ipv6 ospf interface-cost
interface-cost:The range is from 1 to 65535. Default cost is based on the bandwidth.
Specify how the OSPF interface cost is calculated based on the reference bandwidth method. The cost of an interface is
calculated as Reference Bandwidth/Interface speed.
ROUTER OSPFv3
auto-cost [reference-bandwidth ref-bw]
To return to the default bandwidth or to assign cost based on the interface type, use the no auto-cost [reference-
bandwidth ref-bw] command.
ref-bw: The range is from 1 to 4294967. The default is 100 megabits per second.
Open Shortest Path First (OSPFv2 and OSPFv3)
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