OSPFv3

In this section:

  1. OSPFv3 Overview
    Open Shortest Path First (OSPF) is a link-state routing protocol. Each OSPF device originates link-state advertisement (LSA) packets to describe its link information. These LSAs are flooded throughout the OSPF area. The flooding algorithm ensures that every device in the area has an identical database. Each device in the area then calculates a Shortest Path Tree (SPT) that shows the shortest distance to every other device in the area, using the topology information in the Link State database.
  2. Configuring the router ID
    When configuring OSPFv3, the router ID for a device must be specified.
  3. Enabling OSPFv3
    When OSPFv3 is enabled on a device, the device enters OSPFv3 router configuration mode. Several commands can then be accessed that allow the configuration of OSPFv3.
  4. Configuring OSPFv3
    A number of steps are required when configuring OSPFv3:
  5. OSPFv3 areas
    After OSPFv3 is enabled, you can assign OSPFv3 areas. You can specify the area id in plain number format , such as "area 1", or in ipv4 address format, such as 10.1.1.1. Each device interface can support one area.
  6. Virtual Links
    All ABRs must have either a direct or indirect link to an OSPFv3 backbone area (0 or 0.0.0.0). If an ABR does not have a physical link to a backbone area, you can configure a virtual link from the ABR to another router within the same area that has a physical connection to the backbone area.
  7. OSPFv3 route redistribution
    Routes from various sources can be redistributed into OSPFv3. These routes can be redistributed in a number of ways.
  8. Default route origination
    When the device is an OSPFv3 Autonomous System Boundary Router (ASBR), you can configure it to automatically generate a default external route into an OSPFv3 routing domain.
  9. Disabling and re-enabling OSPFv3 event logging
    OSPFv3 event logging, such as neighbor state changes and database overflow conditions, can be disabled and re-enabled.
  10. Filtering OSPFv3 Routes
  11. SPF timers
    The device uses an SPF delay timer and an SPF hold-time timer to calculate the shortest path for OSPFv3 routes. The values for both timers can be changed.
  12. OSPFv3 administrative distance
    Devices can learn about networks from various protocols and select a route based on the source of the route information. This decision can be influenced if the default administrative distance for OSPFv3 routes is changed. Consequently, the routes to a network may differ depending on the protocol from which the routes were learned.
  13. Changing the reference bandwidth for the cost on OSPFv3 interfaces
    The reference bandwidth for OSPFv3 can be altered, resulting in various costs.
  14. OSPFv3 LSA refreshes
    To prevent a refresh from being performed each time an individual LSA's refresh timer expires, OSPFv3 LSA refreshes are delayed for a specified time interval. This pacing interval can be altered.
  15. External route summarization
    An ASBR can be configured to advertise one external route as an aggregate for all redistributed routes that are covered by a specified IPv6 summary address range.
  16. OSPFv3 over VRF
  17. Setting all OSPFv3 interfaces to the passive state
    All OSPFv3 interfaces can be set as passive, causing them to drop all OSPFv3 control packets.
  18. OSPFv3 Graceful Restart Helper
    The OSPFv3 graceful restart (GR) helper provides a device with the capability to participate in a graceful restart in helper mode so that it assists a neighboring routing device that is performing a graceful restart.
  19. OSPFv3 non-stop routing
    OSPFv3 can continue operation without interruption during hitless failover when the NSR feature is enabled.
  20. Configuring the Maximum Number of LSAs in the LSDB for OSPFv3
    New task for 08.0.95
    The maximum number of link state advertisements (LSAs) in the link state database (LSDB) can be configured for OSPFv3. The following task sets the maximum number of LSAs in the LSDB to 20000.
  21. Checking the LSDB Overflow State for OSPFv3
    New task for 08.0.95
    The period of time that needs to pass before a router checks the link state database (LSDB) overflow state can be configured. The following example configures the router to check the LSDB overflow state every 1500 seconds for OSPFv3.
  22. OSPFv3 Authentication
    OSFPv3 can be configured to authenticate packets using one of the following authentication methods:
  23. Displaying OSPFv3 Results
    The show ipv6 ospf command and its variations can be used to display information about OSPFv3 configurations.