Supports IPv4 OSPFv3

introduction

Open Shortest Path First (OSPF) is a routing protocol for IP. It is a link-state protocol, as opposed to a distance-vector protocol. A link-state protocol makes routing decisions based on the link status of source and destination devices. The status of a connection is a description of that interface and its relationship with neighboring network devices. Interface information includes the IPv6 prefix of the interface, the network mask, the type of network it is connected to, the routers that are connected to that network, and so on. This information is disseminated in various types of Link State Indicators (LSAs) .

OSPF version 3, which is described in RFC 2740, supports IPv6.

requirements

conditions

Before enabling OSPF for IPv6 on an interface, you must do the following:

  • Complete the OSPF network strategy and planning for your IPv6 network. For example, you need to decide if multiple areas are required.

  • Enable IPv6 unicast routing.

  • Enable IPv6 on the interface.

  • Configure the IP Security (IPsec) Secure Socket Application Program Interface (API) on OSPF for IPv6 to enable authentication and encryption.

Components used

This document is not limited to specific software and hardware versions.

The information in this document was produced by the devices in a specific laboratory environment. All devices used in this document started with an empty (standard) configuration. With your network up and running, make sure you understand the potential implications of a command.

Conventions

For more information about document conventions, see Cisco Technical Tips Conventions.

Configure

This section provides information on how to configure the features described in this document.

Note: Use the Command Lookup Tool (registered customers only) for more information about the commands used in this document.

Network diagram

The following network setup is used in this document:

configuration

This is the configuration of OSPFv3 for the routers shown in the diagram:

Stub router
ipv6 unicast routing ipv6 cef! interface serial 0/0 no ip address ipv6 enable ipv6 address 2001: ABAB :: / 64 eui-64 ipv6 ospf 1 area 2! ipv6 router ospf 1 router-id 3.3.3.3 area 2 stub!
ABR1 router
ipv6 unicast routing ipv6 cef! interface FastEthernet0 / 0 no ip address speed auto ipv6 address 2003 :: 1/124 ipv6 enable ipv6 ospf 1 area 0! interface Serial0 / 0 no ip address ipv6 address 2002: ABAB :: / 64 eui-64 ipv6 enable ipv6 ospf 1 area 2! ipv6 router ospf 1 router-id 1.1.1.1 area 2 stub no-summary!
ASBR router
ipv6 unicast routing ipv6 cef! interface FastEthernet0 / 0 no ip address ipv6 address 2003 :: 2/124 ipv6 enable ipv6 ospf 1 area 0! interface Serial0 / 0 no ip address ipv6 address 2003 :: 1: 1/124 ipv6 enable ipv6 rip EXT enable! ipv6 router ospf 1 router-id 2.2.2.2 default-metric 25 redistribute rip EXT metric-type 1 include-connected! ipv6 router rip EXT redistribute ospf 1 match internal external 1 external 2 include-connected!
External router
ipv6 unicast routing ipv6 cef! interface Loopback0 no ip address ipv6 address 2004: ABAB :: / 64 eui-64 ipv6 enable ipv6 rip EXT enable! interface Serial0 / 0 no ip address ipv6 address 2003 :: 1: 2/124 ipv6 enable ipv6 rip EXT enable! ipv6 router rip EXT

Check

This section verifies that your configuration is working properly.

The Output Interpreter Tool (registered customers only) (OIT) supports certain showCommands. Use the OIT to do an analysis of the Edition of the Command show.

The Command show ipv6 ospf database) shows the Link State Database (LSDB) of the router.

Stub_Router #show ipv6 ospf database OSPFv3 Router with ID (3.3.3.3) (Process ID 1) Router Link States (Area 2) ADV Router Age Seq # Fragment ID Link count Bits 1.1.1.1 885 0x80000007 0 1 B 3.3.3.3 919 0x80000008 0 1 None Inter Area Prefix Link States (Area 2) ADV Router Age Seq # Prefix 1.1.1.1 373 0x80000002 :: / 0 Link (Type-8) Link States (Area 2) ADV Router Age Seq # Link ID Interface 1.1.1.1 964 0x80000006 5 Se0 / 0 3.3.3.3 1165 0x80000006 5 Se0 / 0 Intra Area Prefix Link States (Area 2) ADV Router Age Seq # Link ID Ref-lstype Ref-LSID 1.1.1.1 964 0x80000005 0 0x2001 0 3.3.3.3 1172 0x80000005 0 0x2001 0

The Show ipv6 ospf database router self-originate command specifies the router LSAs from which the router originates and receives. The router LSAs do not contain any address or prefix information.

Stub_Router # OSPFv3 Router with ID (3.3.3.3) (Process ID 1) Router Link States (Area 2) Routing Bit Set on this LSA LS age: 753 Options: (V6-Bit R-bit DC-Bit) LS Type: Router Links Link State ID: 0 Advertising router: 1.1.1.1 LS Seq Number: 80000007 Checksum: 0xFCA4 Length: 40 Area Border Router Number of Links: 1 Link connected to: another Router (point-to-point) Link Metric: 64 Local Interface ID: 5 Neighbor Interface ID: 5 Neighbor Router ID: 3.3.3.3 LS age: 791 Options: (V6-Bit R-bit DC-Bit) LS Type: Router Links Link State ID: 0 Advertising Router: 3.3.3.3 LS Seq Number: 80000008 Checksum: 0x178A Length: 40 Number of Links : 1 Link connected to: another router (point-to-point) Link Metric: 64 Local Interface ID: 5 Neighbor Interface ID: 5 Neighbor Router ID: 1.1.1.1

The LSAs contain an "Options" field with the following bits:

  • V6 bit: Specifies whether the router / connection should be used for the routing calculation.

  • R bit - This is the "router bit". It indicates whether the starting point is an active router.

  • DC bit (Direct currentbit): Shows how the router handles the demand circuit.

The Command show ipv6 ospf database link self-originate shows that link LSAs contain connection-specific addresses.

Stub_Router #show ipv6 ospf database link self-originate OSPFv3 Router with ID (3.3.3.3) (Process ID 1) Link (Type-8) Link States (Area 2) LS age: 627 Options: (V6-Bit R-bit DC-Bit) LS Type: Link-LSA ( Interface: Serial0 / 0) Link State ID: 5 (Interface ID) Advertising router: 1.1.1.1 LS Seq Number: 80000006 Checksum: 0x215C Length: 56 Router Priority: 1 Link Local Address: FE80 :: D20E: 16FF: FE50: 0 Number of Prefixes: 1 Prefix Address: 2002: ABAB :: Prefix Length: 64, Options: None LS age: 828 Options: (V6-Bit R-bit DC-Bit) LS Type: Link-LSA (Interface: Serial0 / 0 ) Link State ID: 5 (Interface ID) Advertising Router: 3.3.3.3 LS Seq Number: 80000006 Checksum: 0xB4C2 Length: 56 Router Priority: 1 Link Local Address: FE80 :: D20D: 16FF: FE50: 0 Number of Prefixes: 1 Prefix Address: 2001: ABAB :: Prefix Length: 64, Options: None

Since the stub router belongs to a totally stub area, the ABR1 router only sends the standard route to the stub router.

Stub_Router #show ipv6 route IPv6 Routing Table - 6 entries Codes: C - Connected, L - Local, S - Static, R - RIP, B - BGP U - Per-user Static route I1 - ISIS L1, I2 - ISIS L2, IA - ISIS interarea, IS - ISIS summary O - OSPF intra, OI - OSPF inter, OE1 - OSPF ext 1, OE2 - OSPF ext 2 ON1 - OSPF NSSA ext 1, ON2 - OSPF NSSA ext 2 OI :: / 0 [110/65] via FE80: : D20E: 16FF: FE50: 0, Serial0 / 0 C 2001: ABAB :: / 64 [0/0] via ::, Serial0 / 0 L 2001: ABAB :: D20D: 16FF: FE50: 0/128 [0 / 0] via ::, Serial0 / 0 O 2002: ABAB :: / 64 [110/128] via FE80 :: D20E: 16FF: FE50: 0, Serial0 / 0 L FE80 :: / 10 [0/0] via: :, Null0 L FF00 :: / 8 [0/0] via ::, Null0

The ABR1 router is the area border router.

ABR1 #show ipv6 ospf Routing process "ospfv3 1" with ID 1.1.1.1 It is an area border router SPF schedule delay 5 secs, Hold time between two SPFs 10 secs Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs LSA group pacing timer 240 secs Interface flood pacing timer 33 msecs Retransmission pacing timer 66 msecs Number of external LSA 2. Checksum Sum 0x00A1E0 Number of areas in this router is 2. 1 normal 1 stub 0 nssa Reference bandwidth unit is 100 mbps Area BACKBONE (0) Number of interfaces in this area is 1 SPF algorithm executed 5 times Number of LSA 8. Checksum Sum 0x052E71 Number of DCbitless LSA 0 Number of indication LSA 0 Number of DoNotAge LSA 0 Flood list length 0 Area 2 Number of interfaces in this area is 1 It is a stub area, no summary LSA in this area generates stub default route with cost 1 SPF algorithm executed 6 times Number of LSA 7. Checksum Sum 0x042237 Number of DCbitless LSA 0 Number of indication LSA 0 Number of DoNotAge LSA 0 Flood list length 0

The ABR1 router receives external routes (RIP routes) from the ASBR router.

ABR1 #show ipv6 route IPv6 Routing Table - 9 entries Codes: C - Connected, L - Local, S - Static, R - RIP, B - BGP U - Per-user Static route I1 - ISIS L1, I2 - ISIS L2, IA - ISIS interarea, IS - ISIS summary O - OSPF intra, OI - OSPF inter, OE1 - OSPF ext 1, OE2 - OSPF ext 2 ON1 - OSPF NSSA ext 1, ON2 - OSPF NSSA ext 2 O 2001: ABAB :: / 64 [110/128] via FE80 :: D20D: 16FF: FE50: 0, Serial0 / 0 C 2002: ABAB :: / 64 [0/0] via ::, Serial0 / 0 L 2002: ABAB :: D20E: 16FF: FE50: 0/128 [0/0] via ::, Serial0 / 0 C 2003 :: / 124 [0/0] via ::, FastEthernet0 / 0 L 2003 :: 1/128 [0/0] via ::, FastEthernet0 / 0 OE1 2003 :: 1: 0/124 [110/26] via FE80 :: D20F: BFF: FE24: 0, FastEthernet0 / 0 OE1 2004: ABAB :: / 64 [110/26] via FE80 :: D20F: BFF: FE24: 0, FastEthernet0 / 0 L FE80 :: / 10 [0/0] via ::, Null0 L FF00 :: / 8 [0/0] via ::, Null0

The ASBR router is the autonomous system boundary router for the network. It is connected to the RIP network via the serial 0/0 interface.

ASBR #show ipv6 ospf Routing process "ospfv3 1" with ID 2.2.2.2 It is an autonomous system boundary router Redistributing External Routes (with default metric 25) from, rip with metric-type 1 include-connected SPF schedule delay 5 secs, Hold time between two SPFs 10 secs, Minimum LSA interval 5 secs. Minimum LSA arrival 1 secs LSA group pacing timer 240 secs Interface flood pacing timer 33 msecs Retransmission pacing timer 66 msecs Number of external LSA 2. Checksum Sum 0x00A1E0 Number of areas in this router is 1. 1 normal 0 stub 0 nssa Reference bandwidth unit is 100 mbps Area BACKBONE (0) Number of interfaces in this area is 1 SPF algorithm executed 2 times Number of LSA 8. Checksum Sum 0x052E71 Number of DCbitless LSA 0 Number of indication LSA 0 Number of DoNotAge LSA 0 Flood list length 0 ASBR #show ipv6 rip RIP process "EXT", port 521, multicast group FF02 :: 9, pid 156 Administrative distance is 120. Maximum paths is 16 updates every 30 seconds, expire after 180 Holddown lasts 0 seconds, garbage collect after 120 Split horizon is on; poison reverse is off Default routes are not generated Periodic updates 69, trigger updates 6 Interfaces: Serial0 / 0 Redistribution: Redistributing protocol ospf 1 include-connected

Troubleshooting

This section provides troubleshooting for your configuration.

Note: Before using DebugCommands the information about debug commands.

debug IPv6

As soon as OSPFv3 is activated on the stub router, it sends OSPFv3 Type 1 Hello messages to the multicast address FF02 :: 5. As soon as it receives hello packets from the ABR1 router, they negotiate the master / slave relationship and then send DBD packets.

Stub_Router # debug ipv6 ospf eventsStub_Router # debug ipv6 ospf packet * Mar 1 00: 14: 20.999: OSPFv3: rcv. v: 3 t: 1 l: 36 rid: 1.1.1.1 aid: 0.0.0.2 chk: 142A inst: 0 from Serial0 / 0 * Mar 1 00: 14: 21.023: OSPFv3: rcv. v: 3 t: 2 l: 28 rid: 1.1.1.1 aid: 0.0.0.2 chk: EB8A inst: 0 from Serial0 / 0 * Mar 1 00: 14: 21.027: OSPFv3: rcv. v: 3 t: 1 l: 40 rid: 1.1.1.1 aid: 0.0.0.2 chk: E1C inst: 0 from Serial0 / 0 * Mar 1 00: 14: 21.027: OSPFv3: 2 Way Communication to 1.1.1.1 on Serial0 / 0, state 2WAY * Mar 1 00: 14: 21.027: OSPFv3: Send DBD to 1.1.1.1 on Serial0 / 0 seq 0x1737 opt 0x0011flag 0x7 len 28 * Mar 1 00: 14: 21.031: OSPFv3: Rcv DBD from 1.1.1.1 on Serial0 / 0 seq 0x2402 opt 0x0011flag 0x7 len 28 mtu 1500 state EXSTART * Mar 1 00: 14: 21.031: OSPFv3: First DBD and we are not SLAVE * Mar 1 00: 14: 21.035: OSPFv3: rcv. v: 3 t: 2 l: 88 rid: 1.1.1.1 aid: 0.0.0.2 chk: 5CF3 inst: 0 from Serial0 / 0 * Mar 1 00: 14: 21.039: OSPFv3: Rcv DBD from 1.1.1.1 on Serial0 / 0 seq 0x1737 opt 0x0011 flag 0x2 len 88 mtu 1500 state EXSTART * Mar 1 00: 14: 21.039: OSPFv3: NBR Negotiation Done. We are the MASTER * Mar 1 00: 14: 21.039: OSPFv3: Send DBD to 1.1.1.1 on Serial0 / 0 seq 0x1738 opt 0x0011 flag 0x3 len 88 * Mar 1 00: 14: 21.043: OSPFv3: rcv. v: 3 t: 2 l: 28 rid: 1.1.1.1 aid: 0.0.0.2 chk: F85B inst: 0 from Serial0 / 0 * Mar 1 00: 14: 21.047: OSPFv3: Rcv DBD from 1.1.1.1 on Serial0 / 0 seq 0x1738 opt 0x0011 flag 0x0 len 28 mtu 1500 state EXCHANGE * Mar 1 00: 14: 21.047: OSPFv3: Send DBD to 1.1.1.1 on Serial0 / 0 seq 0x1739 opt 0x0011 flag 0x1 len 28Send LS REQ to 1.1.1.1 length 36 LSA count 3 * Mar 1 00: 14: 21.051: OSPFv3: rcv. v: 3 t: 3 l: 52 rid: 1.1.1.1 aid: 0.0.0.2 chk: C326 inst: 0 from Serial0 / 0 * Mar 1 00: 14: 21.055: OSPFv3: rcv. v: 3 t: 2 l: 28 rid: 1.1.1.1 aid: 0.0.0.2 chk: F85A inst: 0 from Serial0 / 0

As soon as the DBD packets have been exchanged, the routers send Link-State Request (LS REQ) and Link-State Update (LS UPD) messages to create their LSDB. After successive LS REQ and LS UPD messages and when the status reaches VULL, the routers continue to exchange hello packets.

Stub_Router # * Mar 1 00: 14: 21.055: OSPFv3: rcv. v: 3 t: 4 l: 144 rid: 1.1.1.1 aid: 0.0.0.2 chk: 58BC inst: 0 from Serial0 / 0Rcv LS REQ from 1.1.1.1 on Serial0 / 0 length 52 LSA count 3Send UPD to 131.88.101.156 on Serial0 / 0 length 128 LSA count 3 * Mar 1 00: 14: 21.059: OSPFv3: Rcv DBD from 1.1.1.1 on Serial0 / 0 seq 0x1739 opt 0x0011 flag 0x0 len 28 mtu 1500 state EXCHANGE * Mar 1 00 : 14: 21.063: OSPFv3: Exchange Done with 1.1.1.1 on Serial0 / 0Rcv LS UPD from 1.1.1.1 on Serial0 / 0 length 144 LSA count 3 * Mar 1 00: 14: 21.067: OSPFv3: Synchronized with 1.1.1.1 on Serial0 / 0, state FULL * Mar 1 00: 14: 21.067:% OSPFv3-5-ADJCHG: Process 1, Nbr 1.1.1.1 on Serial0 / 0 from LOADING to FULL, Loading Done * Mar 1 00: 14: 21.687: OSPFv3: rcv. v: 3 t: 4 l: 60 rid: 1.1.1.1 aid: 0.0.0.2 chk: 66EB inst: 0 from Serial0 / 0Rcv LS UPD from 1.1.1.1 on Serial0 / 0 length 60 LSA count 1 * Mar 1 00:14 : 23.683: OSPFv3: rcv. v: 3 t: 5 l: 96 rid: 1.1.1.1 aid: 0.0.0.2 chk: 4BB5 inst: 0 from Serial0 / 0

Related information