- Read Me First
- Configuring OSPF
- IPv6 Routing: OSPFv3
- IPv6 Routing: OSPFv3 Authentication Support with IPsec
- OSPFv2 Cryptographic Authentication
- OSPFv3 External Path Preference Option
- OSPFv3 Graceful Restart
- Graceful Shutdown Support for OSPFv3
- OSPF Stub Router Advertisement
- OSPF Update Packet-Pacing Configurable Timers
- OSPF Sham-Link Support for MPLS VPN
- OSPF Support for Multi-VRF on CE Routers
- OSPFv2 Multiarea Adjacency
- OSPFv2 Autoroute Exclude
- OSPFv3 Address Families
- OSPFv3 Authentication Trailer
- Autoroute Announce and Forwarding Adjacencies For OSPFv3
- OSPFv3 Autoroute Exclude
- OSPFv2 IP FRR Local Microloop Avoidance
- OSPFv2-OSPF Live-Live
- OSPF Forwarding Address Suppression in Translated Type-5 LSAs
- OSPF Inbound Filtering Using Route Maps with a Distribute List
- OSPFv3 Route Filtering Using Distribute-List
- OSPF Shortest Path First Throttling
- OSPF Support for Fast Hello Packets
- OSPF Incremental SPF
- OSPF Limit on Number of Redistributed Routes
- OSPFv3 Fast Convergence: LSA and SPF Throttling
- OSPFv3 Max-Metric Router LSA
- OSPF Link-State Advertisement Throttling
- OSPF Support for Unlimited Software VRFs per PE Router
- OSPF Area Transit Capability
- OSPF Per-Interface Link-Local Signaling
- OSPF Link-State Database Overload Protection
- OSPF MIB Support of RFC 1850 and Latest Extensions
- OSPF Enhanced Traffic Statistics
- TTL Security Support for OSPFv3 on IPv6
- Configuring OSPF TTL Security Check and OSPF Graceful Shutdown
- OSPF Sham-Link MIB Support
- OSPF SNMP ifIndex Value for Interface ID in Data Fields
- OSPFv2 Local RIB
- OSPF Support for Forwarding Adjacencies over MPLS TE Tunnels
- Enabling OSPFv2 on an Interface Basis
- OSPF Nonstop Routing
- OSPFv3 NSR
- OSPFv2 Loop-Free Alternate Fast Reroute
- OSPFv3 MIB
- Prefix Suppression Support for OSPFv3
- OSPFv3 VRF-Lite/PE-CE
- OSPFv3 ABR Type 3 LSA Filtering
- OSPFv3 Demand Circuit Ignore
- OSPF IPv4 Remote Loop-Free Alternate IP Fast Reroute
- OSPFv3 Multiarea Adjacency
- OSPF Limiting Adjacency Formations
OSPFv3 NSR
The OSPFv3 NSR feature allows a router with redundant Route Processors (RPs) to maintain its Open Shortest Path First (OSPF) state and adjacencies across planned and unplanned RP switchovers. It does this by checkpointing state information from OSPFv3 on the active RP to the standby RP. Later, following a switchover to the standby RP, OSPFv3 can use this checkpointed information to continue operation without interruption.
- Finding Feature Information
- Information About OSPFv3 NSR
- How to Configure OSPFv3 NSR
- Configuration Examples for OSPFv3 NSR
- Additional References
- Feature Information for OSPFv3 NSR
Finding Feature Information
Your software release may not support all the features documented in this module. For the latest caveats and feature information, see Bug Search Tool and the release notes for your platform and software release. To find information about the features documented in this module, and to see a list of the releases in which each feature is supported, see the feature information table.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.
Information About OSPFv3 NSR
OSPFv3 NSR Functionality
Although OSPFv3 NSR serves a similar function to the OSPFv3 graceful restart feature, it works differently. With graceful restart, OSPFv3 on the newly active standby RP initially has no state information, so it uses extensions to the OSPFv3 protocol to recover its state from neighboring OSPFv3 devices. For this to work, the neighbors must support the graceful restart protocol extensions and be able to act as helpers to the restarting device. They must also continue forwarding data traffic to the restarting device while this recovery is taking place.
With NSR, by contrast, the device performing the switchover preserves its state internally, and in most cases the neighbors are unaware that anything has happened. Because no assistance is needed from neighboring devices, NSR can be used in situations where graceful restart cannot; for example, graceful restart is unreliable in networks where not all the neighbors implement the graceful restart protocol extensions or where the network topology changes during the recovery.
 Note | When NSR is enabled, the responsiveness and scalability of OSPF is degraded. The performance degradation happens because OSPF uses cpu and memory to checkpoint data to the standby Route Processor (RP). |
How to Configure OSPFv3 NSR
Configuring OSPFv3 NSR
Perform this task to configure OSPFv3 NSR.
Note | Devices that do not support NSR will not accept the nsr (OSPFv3) command. |
1.
enable
2.
configure
terminal
3.
router
ospfv3
process-id
4.
nsr
5.
end
6.
show
ospfv3 [process-id] [address-family]
nsr
DETAILED STEPS
Configuring OSPFv3 NSR for an Address Family
In address family configuration mode you can configure NSR for a particular address family. Perform this task to enable OSPFv3 NSR for an address family.
Note | Devices that do not support NSR will not accept the nsr (OSPFv3) command. |
1.
router
ospfv3
process-id
2.
address-family {ipv4 |
ipv6}
unicast [vrf
vrf-name]
3.
nsr [disable]
DETAILED STEPS
Disabling OSPFv3 NSR for an Address Family
In address family configuration mode the optional disable keyword is available for the nsr command. Perform this task to disable OSPFv3 NSR for an address family.
1.
router
ospfv3
process-id
2.
address-family {ipv4 |
ipv6}
unicast [vrf
vrf-name]
3.
nsr [disable]
DETAILED STEPS
Troubleshooting Tips
OSPFv3 NSR can increase the amount of memory used by the OSPFv3 device process. To determine how much memory OSPFv3 is currently using without NSR, you can use the show processes and show processes memory commands:
Device# show processes | include OSPFv3 276 Mwe 133BE14 1900 1792 1060 8904/12000 0 OSPFv3-1 Router 296 Mwe 133A824 10 971 10 8640/12000 0 OSPFv3-1 Hello
Process 276 is the OSPFv3 device process that is to be checked. The show processes memory command is used to display its current memory use:
Device# show processes memory 276 Process ID: 276 Process Name: OSPFv3-1 Router Total Memory Held: 4454800 bytes
In this case OSPFv3 is using 4,454,800 bytes or approximately 4.5 megabytes (MB). OSPFv3 NSR could double this for brief periods, so you should make sure the device has at least 5 MB of free memory before enabling OSPFv3 NSR.
Configuration Examples for OSPFv3 NSR
Example Configuring OSPFv3 NSR
The following example shows how to configure OSPFv3 NSR and verify that it is enabled:
Device(config)# router ospfv3 1
Device(config-router)# nsr
Device(config-router)# end
Device# show ospfv3 1
OSPFv3 1 address-family ipv4
Router ID 10.0.0.1
Supports NSSA (compatible with RFC 3101)
Event-log enabled, Maximum number of events: 1000, Mode: cyclic
It is an area border and autonomous system boundary router
Redistributing External Routes from,
Router is not originating router-LSAs with maximum metric
Initial SPF schedule delay 5000 msecs
Minimum hold time between two consecutive SPFs 10000 msecs
Maximum wait time between two consecutive SPFs 10000 msecs
Minimum LSA interval 5 secs
Minimum LSA arrival 1000 msecs
LSA group pacing timer 240 secs
Interface flood pacing timer 33 msecs
Retransmission pacing timer 66 msecs
Retransmission limit dc 24 non-dc 24
Number of external LSA 0. Checksum Sum 0x000000
Number of areas in this router is 3. 2 normal 0 stub 1 nssa
Non-Stop Routing enabled
Graceful restart helper support enabled
Reference bandwidth unit is 100 mbps
RFC1583 compatibility enabled
Area BACKBONE(0) (Inactive)
Number of interfaces in this area is 1
SPF algorithm executed 3 times
Number of LSA 6. Checksum Sum 0x03C938
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
Area 1
Number of interfaces in this area is 3
SPF algorithm executed 3 times
Number of LSA 6. Checksum Sum 0x024041
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
Area 3
Number of interfaces in this area is 1
It is a NSSA area
Perform type-7/type-5 LSA translation
SPF algorithm executed 4 times
Number of LSA 5. Checksum Sum 0x024910
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
OSPFv3 1 address-family ipv6
Router ID 10.0.0.1
Supports NSSA (compatible with RFC 3101)
Event-log enabled, Maximum number of events: 1000, Mode: cyclic
It is an area border and autonomous system boundary router
Redistributing External Routes from,
ospf 2
Router is not originating router-LSAs with maximum metric
Initial SPF schedule delay 5000 msecs
Minimum hold time between two consecutive SPFs 10000 msecs
Maximum wait time between two consecutive SPFs 10000 msecs
Minimum LSA interval 5 secs
Minimum LSA arrival 1000 msecs
LSA group pacing timer 240 secs
Interface flood pacing timer 33 msecs
Retransmission pacing timer 66 msecs
Retransmission limit dc 24 non-dc 24
Number of external LSA 0. Checksum Sum 0x000000
Number of areas in this router is 3. 2 normal 0 stub 1 nssa
Non-Stop Routing enabled
Graceful restart helper support enabled
Reference bandwidth unit is 100 mbps
RFC1583 compatibility enabled
Area BACKBONE(0) (Inactive)
Number of interfaces in this area is 2
SPF algorithm executed 2 times
Number of LSA 6. Checksum Sum 0x02BAB7
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
Area 1
Number of interfaces in this area is 4
SPF algorithm executed 2 times
Number of LSA 7. Checksum Sum 0x04FF3A
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
Area 3
Number of interfaces in this area is 1
It is a NSSA area
Perform type-7/type-5 LSA translation
SPF algorithm executed 3 times
Number of LSA 5. Checksum Sum 0x011014
Number of DCbitless LSA 0
Number of indication LSA 0
Number of DoNotAge LSA 0
Flood list length 0
The output shows that OSPFv3 NSR is configured.
Example Verifying OSPFv3 NSR
The following example shows how to verify OSPFv3 NSR status:
Device# show ospfv3 1 nsr
Active RP
Operating in duplex mode
Redundancy state: ACTIVE
Peer redundancy state: STANDBY HOT
Checkpoint peer ready
Checkpoint messages enabled
ISSU negotiation complete
ISSU versions compatible
OSPFv3 1 address-family ipv4 (router-id 10.0.0.1)
NSR configured
Checkpoint message sequence number: 29
Standby synchronization state: synchronized
Bulk sync operations: 1
Next sync check time: 12:00:14.956 PDT Wed Jun 6 2012
LSA Count: 17, Checksum Sum 0x00085289
OSPFv3 1 address-family ipv6 (router-id 10.0.0.1)
NSR configured
Checkpoint message sequence number: 32
Standby synchronization state: synchronized
Bulk sync operations: 1
Next sync check time: 12:00:48.537 PDT Wed Jun 6 2012
LSA Count: 18, Checksum Sum 0x0008CA05
The output shows that OSPFv3 NSR is configured and that OSPFv3 on the standby RP is fully synchronized and ready to continue operation if the active RP fails or if a manual switchover is performed.
Additional References
Related Documents
|
Related Topic |
Document Title |
|---|---|
|
Cisco IOS commands |
|
|
OSPF commands |
Cisco IOS IP Routing: OSPF Command Reference |
|
OSPFv3 Address Families |
OSPFv3 Address Families module |
Standards
|
Standards |
Title |
|---|---|
|
No new or modified standards are supported by this feature, and support for existing standards has not been modified by this feature. |
— |
MIBs
|
MIBs |
MIBs Link |
|---|---|
|
No new or modified MIBs are supported by this feature, and support for existing MIBs has not been modified by this feature. |
To locate and download MIBs for selected platforms, Cisco software releases, and feature sets, use Cisco MIB Locator found at the following URL: |
RFCs
|
RFCs |
Title |
|---|---|
|
RFC 5187. |
OSPFv3 Graceful Restart |
Technical Assistance
|
Description |
Link |
|---|---|
|
The Cisco Support and Documentation website provides online resources to download documentation, software, and tools. Use these resources to install and configure the software and to troubleshoot and resolve technical issues with Cisco products and technologies. Access to most tools on the Cisco Support and Documentation website requires a Cisco.com user ID and password. |
Feature Information for OSPFv3 NSR
The following table provides release information about the feature or features described in this module. This table lists only the software release that introduced support for a given feature in a given software release train. Unless noted otherwise, subsequent releases of that software release train also support that feature.
Use Cisco Feature Navigator to find information about platform support and Cisco software image support. To access Cisco Feature Navigator, go to www.cisco.com/go/cfn. An account on Cisco.com is not required.|
Feature Name |
Releases |
Feature Information |
|---|---|---|
|
OSPFv3 NSR |
15.1(2)SY 15.2(4)S |
The OSPFv3 NSR feature allows a router with redundant RPs to maintain its OSPFv3 state and adjacencies across planned and unplanned RP switchovers. The following commands were introduced or modified: clear ospfv3 nsr, nsr (OSPFv3), show ospfv3 nsr. |
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