Open Shortest Path First v3 - OSPFv3

OSPFv3 is a revised version of OSPFv2 and supports the IPv6 address family.

IETF has defined extensions to OSPFv3 to support multiple address families (both IPv6 and IPv4). FRR does not currently support multiple address families.

Basic OSPFv3 Configuration

You can configure OSPFv3 using either numbered interfaces or unnumbered interfaces. Both methods are described below.

OSPFv3 Numbered

To configure OSPF using numbered interfaces, you specify the router ID, IP subnet prefix, and area address. All the interfaces on the switch with an IP address that matches the network subnet are put into the specified area. OSPF attempts to discover other OSPF routers on those interfaces. All matching interface network addresses are added to a Type-1 Router LSA and advertised to discovered neighbors for proper reachability.

If you do not want to bring up an OSPF adjacency on certain interfaces, but want to advertise those networks in the OSPF database, you can configure the interfaces as passive interfaces. A passive interface creates a database entry but does not send or recieve OSPF hello packets. For example, in a data center topology, the host-facing interfaces do not need to run OSPF, however, the corresponding IP addresses still need to be advertised to neighbors.

The following example commands configure OSPF numbered on leaf01 and spine01.

leaf01spine01
  • The loopback address is 2001:db8::a0a:0a01/128
  • The IP address on swp51 is 2001:db8::a00:0101/127
  • The router ID is 10.10.10.1
  • All the interfaces on the switch with an IP address that matches subnet 2001:db8::a0a:0a01/128 and swp51 with IP address 2001:db8::a00:0101/127 are in area 0.0.0.0
  • swp1 and swp2 are passive interfaces
  • The loopback address is 2001:db8::a0a:0a65/128
  • The IP address on swp1 is 22001:db8::a00:0100/127
  • The router ID is 10.10.10.101
  • All interfaces on the switch with an IP address that matches subnet 2001:db8::a0a:0a65/128 and swp1 with IP address 2001:db8::a00:0100/127 are in area 0.0.0.0.
cumulus@leaf01:~$ net add loopback lo ip address 2001:db8::a0a:0a01/128
cumulus@leaf01:~$ net add interface swp51 ip address 2001:db8::a00:0101/127
cumulus@leaf01:~$ net add ospf6 router-id 10.10.10.1
cumulus@leaf01:~$ net add ospf6 interface lo area 0.0.0.0
cumulus@leaf01:~$ net add ospf6 interface swp51 area 0.0.0.0
cumulus@leaf01:~$ net add interface swp1 ospf6 passive
cumulus@leaf01:~$ net add interface swp2 ospf6 passive
cumulus@leaf01:~$ net pending
cumulus@leaf01:~$ net commit
cumulus@spine01:~$ net add loopback lo ip address 2001:db8::a0a:0a65/128
cumulus@spine01:~$ net add interface swp1 ip address 2001:db8::a00:0100/127
cumulus@spine01:~$ net add ospf6 router-id 10.10.10.101
cumulus@spine01:~$ net add ospf6 interface lo area 0.0.0.0
cumulus@spine01:~$ net add ospf6 interface swp1 area 0.0.0.0
cumulus@spine01:~$ net pending
cumulus@spine01:~$ net commit
  1. Edit the /etc/frr/daemons file to enable the ospf6 daemon, then start the FRRouting service (see Configure FRRouting).

  2. Edit the /etc/network/interfaces file to configure the IP address for the loopback and swp51:

cumulus@leaf01:~$ sudo nano /etc/network/interfaces
...
auto lo
iface lo inet loopback
  address 2001:db8::a0a:0a01/128

auto swp51 iface swp51 address 2001:db8::a00:0101/127

  1. Run the ifreload -a command to load the new configuration:

    cumulus@leaf01:~$ sudo ifreload -a
    
  2. From the vtysh shell, configure OSPF:

    cumulus@leaf01:~$ sudo vtysh
    

    leaf01# configure terminal leaf01(config)# router ospf6 leaf01(config-ospf6)# ospf6 router-id 10.10.10.1 leaf01(config-ospf6)# interface lo area 0.0.0.0 leaf01(config-ospf6)# interface swp51 area 0.0.0.0 leaf01(config-ospf6)# exit leaf01(config)# interface swp1 leaf01(config-if)# ipv6 ospf6 passive leaf01(config-if)# exit leaf01(config)# interface swp2 leaf01(config-if)# ipv6 ospf6 passive leaf01(config-if)# end leaf01# write memory leaf01# exit cumulus@leaf01:~$

  1. Edit the /etc/frr/daemons file to enable the ospf6 daemon, then start the FRRouting service (see Configure FRRouting).

  2. Edit the /etc/network/interfaces file to configure the IP address for the loopback and swp1:

    cumulus@spine01:~$ sudo nano /etc/network/interfaces
    ...
    auto lo
    iface lo inet loopback
      address 2001:db8::a0a:0a65/128
    

    auto swp1 iface swp1 address 2001:db8::a00:0100/127

  3. Run the ifreload -a command to load the new configuration:

    cumulus@spine01:~$ sudo ifreload -a
    
  4. From the vtysh shell, configure OSPF:

    cumulus@spine01:~$ sudo vtysh
    

    spine01# configure terminal spine01(config)# router ospf6 spine01(config-ospf6)# ospf6 router-id 10.10.10.101 spine01(config-ospf6)# interface lo area 0.0.0.0 spine01(config-ospf6)# interface swp1 area 0.0.0.0 spine01(config-ospf6)# end spine01# write memory spine01# exit cumulus@spine01:~$

The NCLU and vtysh commands save the configuration in the /etc/frr/frr.conf file. For example:

...
router ospf6
 ospf6 router-id 10.10.10.1
 interface lo area 0.0.0.0
 interface swp51 area 0.0.0.0
interface swp1
 ipv6 ospf6 passive
interface swp2
 ipv6 ospf6 passive
...
...
router ospf6
 ospf router-id 10.10.10.101
 interface lo area 0.0.0.0
 interface swp1 area 0.0.0.0
...

OSPFv3 Unnumbered

Unnumbered interfaces are interfaces without unique IP addresses; multiple interfaces share the same IP address.

To configure an unnumbered interface, take the IP address of another interface (called the anchor) and use that as the IP address of the unnumbered interface. The anchor is typically the loopback interface on the switch.

OSPFv3 Unnumbered is supported with point-to-point interfaces only.

The following example commands configure OSPFv3 unnumbered on leaf01 and spine01.

leaf01spine01
  • The loopback address is 2001:db8::a0a:0a01/128
  • The router ID is 10.10.10.1
  • OSPF is enabled on the loopback interface and on swp51 in area 0.0.0.0
  • swp1 and swp2 are passive interfaces
  • swp51 is a point-to-point interface (point-to-point is required for unnumbered interfaces)
    • The loopback address is 2001:db8::a0a:0a65/128
    • The router ID is 10.10.10.101
    • OSPF is enabled on the loopback interface and on swp1 in area 0.0.0.0
    • swp1 is a point-to-point interface (point-to-point is required for unnumbered interfaces)
      cumulus@leaf01:~$ net add loopback lo ip address 2001:db8::a0a:0a01/128
      cumulus@leaf01:~$ net add interface swp51 ip address 2001:db8::a0a:0a01/128
      cumulus@leaf01:~$ net add ospf6 router-id 10.10.10.1
      cumulus@leaf01:~$ net add ospf6 interface lo area 0.0.0.0
      cumulus@leaf01:~$ net add ospf6 interface swp51 area 0.0.0.0
      cumulus@leaf01:~$ net add interface swp1 ospf6 passive
      cumulus@leaf01:~$ net add interface swp2 ospf6 passive
      cumulus@leaf01:~$ net add interface swp51 ospf6 network point-to-point
      cumulus@leaf01:~$ net pending
      cumulus@leaf01:~$ net commit
      
      cumulus@spine01:~$ net add loopback lo ip address 2001:db8::a0a:0a65/128
      cumulus@spine01:~$ net add interface swp1 ip address 2001:db8::a0a:0a65/128
      cumulus@spine01:~$ net add ospf6 router-id 10.10.10.101
      cumulus@spine01:~$ net add ospf6 interface lo area 0.0.0.0
      cumulus@spine01:~$ net add ospf6 interface swp1 area 0.0.0.0
      cumulus@spine01:~$ net add interface swp1 ospf6 network point-to-point
      cumulus@spine01:~$ net pending
      cumulus@spine01:~$ net commit
      
      1. Edit the /etc/frr/daemons file to enable the ospf6 daemon, then start the FRRouting service (see Configure FRRouting).

      2. Edit the /etc/network/interfaces file to configure the IP address for the loopback and swp51:

      cumulus@leaf01:~$ sudo nano /etc/network/interfaces
      ...
      auto lo
      iface lo inet loopback
        address 2001:db8::a0a:0a01/128
      

      auto swp1 iface swp1 address 2001:db8::a0a:0a01/128

      1. Run the ifreload -a command to load the new configuration:

        cumulus@leaf01:~$ sudo ifreload -a
        

      2. From the vtysh shell, configure OSPFv3:

      cumulus@leaf01:~$ sudo vtysh
      

      leaf01# configure terminal leaf01(config)# router ospf6 leaf01(config-ospf6)# ospf6 router-id 10.10.10.1 leaf01(config-ospf6)# interface lo area 0.0.0.0 leaf01(config-ospf6)# interface swp51 area 0.0.0.0 leaf01(config-ospf6)# exit leaf01(config)# interface swp1 leaf01(config-if)# ipv6 ospf6 passive leaf01(config-if)# exit leaf01(config)# interface swp2 leaf01(config-if)# ipv6 ospf6 passive leaf01(config-if)# exit leaf01(config)# interface swp51 leaf01(config-if)# ipv6 ospf6 network point-to-point leaf01(config-if)# end leaf01# write memory leaf01# exit cumulus@leaf01:~$

      1. Edit the /etc/frr/daemons file to enable the ospf6 daemon, then start the FRRouting service (see Configure FRRouting).

      2. Edit the /etc/network/interfaces file to configure the IP address for the loopback and swp1:

      cumulus@spine01:~$ sudo nano /etc/network/interfaces
      ...
      auto lo
      iface lo inet loopback
        address 2001:db8::a0a:0a65/128
      

      auto swp1 iface swp1 address 2001:db8::a0a:0a65/128

      1. Run the ifreload -a command to load the new configuration:

        cumulus@spine01:~$ sudo ifreload -a
        
      2. From the vtysh shell, configure OSPFv3:

      cumulus@spine01:~$ sudo vtysh
      

      spine01# configure terminal spine01(config)# router ospf6 spine01(config-ospf6)# ospf router-id 10.10.10.101 spine01(config-ospf6)# interface lo area 0.0.0.0 spine01(config-ospf6)# interface swp1 area 0.0.0.0 spine01(config-ospf6)# exit spine01(config)# interface swp1 spine01(config-if)# ipv6 ospf6 network point-to-point spine01(config-if)# end spine01# write memory spine01# exit cumulus@spine01:~$

      The NCLU and vtysh commands save the configuration in the /etc/frr/frr.conf file. For example:

      ...
      router ospf6
       ospf6 router-id 10.10.10.1
       interface lo area 0.0.0.0
       interface swp51 area 0.0.0.0
      interface swp1
       ipv6 ospf6 passive
      interface swp2
       ipv6 ospf6 passive
      interface swp51
       ipv6 ospf6 network point-to-point
      ...
      
      ...
      router ospf6
       ospf6 router-id 10.10.10.101
       interface lo area 0.0.0.0
       interface swp1 area 0.0.0.0
      interface swp1
       ipv6 ospf6 network point-to-point
      ...
      

      Optional OSPFv3 Configuration

      This section describes optional configuration. The steps provided in this section assume that you already configured basic OSPFv3 as described in Basic OSPF Configuration, above.

      Interface Parameters

      You can define the following OSPF parameters per interface:

      • Network type (point-to-point or broadcast). Broadcast is the default setting. Configure the interface as point-to-point unless you intend to use the Ethernet media as a LAN with multiple connected routers. Point-to-point provides a simplified adjacency state machine; there is no need for DR/BDR election and LSA reflection. See RFC5309 for a more information.

        Point-to-point is required for OSPFv3 unnumbered.

      • Hello interval. The number of seconds between hello packets sent on the interface. The default is 10 seconds.
      • Dead interval. Then number of seconds before neighbors declare the router down after they stop hearing hello packets. The default is 40 seconds.
      • Priority in becoming the OSPF Designated Router (DR) on a broadcast interface. The default is priority 1.
      • Advertise prefix list. The prefix list defines the outbound route filter.
      • Cost. The cost determines the shortest paths to the destination.

      The following command example sets the network type to point-to-point on swp51.

      cumulus@switch:~$ net add interface swp51 ospf6 network point-to-point
      cumulus@switch:~$ net pending
      cumulus@switch:~$ net commit
      
      cumulus@switch:~$ sudo vtysh
      
      switch# configure terminal
      switch(config)# interface swp51
      switch(config-if)# ipv6 ospf6 network point-to-point
      switch(config-if)# end
      switch# write memory
      switch# exit
      cumulus@switch:~$
      

      The NCLU and vtysh commands save the configuration in the /etc/frr/frr.conf file. For example:

      ...
      interface swp51
       ipv6 ospf6 network point-to-point
      ...
      

      The following command example sets the hello interval to 5 seconds, the dead interval to 60 seconds, and the priority to 5 for swp51. The hello interval and dead inteval can be any value between 1 and 65535 seconds. The priority can be any value between 0 to 255 (0 configures the interface to never become the OSPF Designated Router (DR) on a broadcast interface).

      cumulus@switch:~$ net add interface swp51 ospf6 hello-interval 5
      cumulus@switch:~$ net add interface swp51 ospf6 dead-interval 60
      cumulus@switch:~$ net add interface swp51 ospf6 priority 5
      cumulus@switch:~$ net pending
      cumulus@switch:~$ net commit
      
      cumulus@switch:~$ sudo vtysh
      
      switch# configure terminal
      switch(config)# interface swp51
      switch(config-if)# ipv6 ospf6 hello-interval 5
      switch(config-if)# ipv6 ospf6 network dead-interval 60
      switch(config-if)# ipv6 ospf6 network priority 5
      switch(config-if)# end
      switch# write memory
      switch# exit
      cumulus@switch:~$
      

      The NCLU and vtysh commands save the configuration in the /etc/frr/frr.conf file. For example:

      ...
      interface swp51
       ipv6 ospf6 hello-interval 5
       ipv6 ospf6 dead-interval 60
       ipv6 ospf6 priority 5
      ...
      

      The following example command configures interface swp51 with the IPv6 advertise prefix list named myfilter:

      cumulus@switch:~$ net add interface swp51 ospf6 advertise prefix-list myfilter
      cumulus@switch:~$ net pending
      cumulus@switch:~$ net commit
      
      cumulus@switch:~$ sudo vtysh
      
      switch# configure terminal
      switch(config)# interface swp51
      switch(config-if)# ipv6 ospf6 advertise prefix-list myfilter
      switch(config-if)# end
      switch# write memory
      switch# exit
      cumulus@switch:~$
      

      The NCLU and vtysh commands save the configuration in the /etc/frr/frr.conf file. For example:

      ...
      interface swp51
        ipv6 ospf6 advertise prefix-list myfilter
      ...
      

      The following example command configures the cost for swp51.

      cumulus@switch:~$ net add interface swp51 ospf6 cost 1
      cumulus@switch:~$ net pending
      cumulus@switch:~$ net commit
      
      cumulus@switch:~$ sudo vtysh
      
      switch# configure terminal
      switch(config)# interface swp51
      switch(config-if)# ipv6 ospf6 cost 1
      switch(config-if)# end
      switch# write memory
      switch# exit
      cumulus@switch:~$
      

      The NCLU and vtysh commands save the configuration in the /etc/frr/frr.conf file. For example:

      ...
      interface swp51
        ipv6 ospf6 cost 1
      ...
      

      To show the currently configured OSPF interface parameter values, run the NCLU net show ospf6 interface command or the vtysh show ipv6 ospf6 interface command.

      SPF Timer Defaults

      OSPF3 uses the following default timers to prevent consecutive SPFs from overburdening the CPU:

      • 0 milliseconds from the initial event until SPF runs
      • 50 milliseconds between consecutive SPF runs (the number doubles with each SPF, until it reaches the maximum time between SPF runs)
      • 5000 milliseconds maximum between SPFs

      The following example commands change the number of milliseconds from the initial event until SPF runs to 80, the number of milliseconds between consecutive SPF runs to 100, and the maximum number of milliseconds between SPFs to 6000.

      cumulus@switch:~$ net add ospf6 timers throttle spf 80 100 6000
      cumulus@switch:~$ net pending
      cumulus@switch:~$ net commit
      
      cumulus@switch:~$ sudo vtysh
      
      switch# configure terminal
      switch(config)# router ospf6
      switch(config-ospf6)# timers throttle spf 80 100 6000
      switch(config-ospf6)# end
      switch# write memory
      switch# exit
      cumulus@switch:~$
      

      The NCLU and vtysh commands save the configuration in the /etc/frr/frr.conf file. For example:

      ...
      router ospf6
       ospf router-id 10.10.10.1
       passive-interface swp1
       passive-interface swp2
       network swp51 area 0.0.0.0
       timers throttle spf 80 100 6000
      ...
      

      To see the configured SPF timer values, run the NCLU net show ospf6 command or the vtysh show ipv6 ospf6 command.

      Configure the OSPFv3 Area

      You can use different areas to control routing. You can:

      • Limit an OSPFv3 area from reaching another area.
      • Manage the size of the routing table by creating a summary route for all the routes in a particular address range.

      The following section provides command examples.

      The following example command removes the 3:3::/64 route from the routing table. Without a route in the table, any destinations in that network are not reachable.

      cumulus@switch:~$ net add ospf6 area 0.0.0.0 range 3:3::/64 not-advertise
      cumulus@switch:~$ net pending
      cumulus@switch:~$ net commit
      

      The following example command creates a summary route for all the routes in the range 2001::/64:

      cumulus@switch:~$ net add ospf6 area 0.0.0.0 range 2001::/64 advertise
      cumulus@switch:~$ net pending
      cumulus@switch:~$ net commit
      

      You can also configure the cost for a summary route, which is used to determine the shortest paths to the destination. The value for cost must be between 0 and 16777215.

      cumulus@switch:~$ net add ospf6 area 0.0.0.0 range 2001::/64 cost 160
      cumulus@switch:~$ net pending
      cumulus@switch:~$ net commit
      

      The following example command removes the 3:3::/64 route from the routing table. Without a route in the table, any destinations in that network are not reachable.

      cumulus@switch:~$ sudo vtysh
      
      switch# configure terminal
      switch(config)# router ospf6
      switch(config-ospf6)# area 0.0.0.0 range 3:3::/64 not-advertise
      switch(config-ospf6)# end
      switch# write memory
      switch# exit
      cumulus@switch:~
      

      The following example command creates a summary route for all the routes in the range 2001::/64:

      cumulus@switch:~$ sudo vtysh
      
      switch# configure terminal
      switch(config)# router ospf6
      switch(config-ospf6)# area 0.0.0.0 range 2001::/64 advertise
      switch(config-ospf6)# end
      switch# write memory
      switch# exit
      cumulus@switch:~$
      

      You can also configure the cost for a summary route, which is used to determine the shortest paths to the destination. The value for cost must be between 0 and 16777215.

      cumulus@switch:~$ sudo vtysh
      
      switch# configure terminal
      switch(config)# router ospf6
      switch(config-ospf6)# area 0.0.0.0 range 2001::/64 cost 160
      switch(config-ospf6)# end
      switch# write memory
      switch# exit
      cumulus@switch:~$
      

      The NCLU and vtysh commands save the configuration in the /etc/frr/frr.conf file. For example:

      ...
      router ospf6
        ospf6 router-id 10.10.10.1
        area 0.0.0.0 range 3:3::/64 not-advertise
        area 0.0.0.0 range 2001::/64 advertise
        area 0.0.0.0 range 2001::/64 cost 160
      ...
      

      Stub Areas

      External routes are the routes redistributed into OSPF from another protocol. They have an AS-wide flooding scope. In many cases, external link states make up a large percentage of the link-state database (LSDB). Stub areas reduce the LSDB size by not flooding AS-external LSAs.

      All routers must agree that an area is a stub, otherwise they will not become OSPF neighbors.

      To configure a stub area:

      cumulus@switch:~$ net add ospf6 area 0.0.0.1 stub
      cumulus@switch:~$ net pending
      cumulus@switch:~$ net commit
      
      cumulus@switch:~$ sudo vtysh
      
      switch# configure terminal
      switch(config)# router ospf6
      switch(config-ospf6)# area 0.0.0.1 stub
      switch(config-ospf6)# end
      switch# write memory
      switch# exit
      cumulus@switch:~$
      

      The NCLU and vtysh commands save the configuration in the /etc/frr/frr.conf file. For example:

      ...
      router ospf6
       ospf6 router-id 10.10.10.63
       area 0.0.0.1 stub
      ...
      

      Stub areas still receive information about networks that belong to other areas of the same OSPF domain. If summarization is not configured (or is not comprehensive), the information can be overwhelming for the nodes. Totally stubby areas address this issue. Routers in totally stubby areas keep information about routing within their area in their LSDB.

      To configure a totally stubby area:

      cumulus@switch:~$ net add ospf6 area 0.0.0.1 stub no-summary
      cumulus@switch:~$ net pending
      cumulus@switch:~$ net commit
      
      cumulus@switch:~$ sudo vtysh
      
      switch# configure terminal
      switch(config)# router ospf6
      switch(config-ospf6)# area 0.0.0.1 stub no-summary
      switch(config-ospf6)# end
      switch# write memory
      switch# exit
      cumulus@switch:~$
      

      The NCLU and vtysh commands save the configuration in the /etc/frr/frr.conf file. For example:

      ...
      router ospf6
       ospf6 router-id 10.10.10.63
       area 0.0.0.1 stub no-summary
      ...
      

      Here is a brief summary of the area type differences:

      TypeBehavior
      Normal non-zero areaLSA types 1, 2, 3, 4 area-scoped, type 5 externals, inter-area routes summarized
      Stub areaLSA types 1, 2, 3, 4 area-scoped, no type 5 externals, inter-area routes summarized
      Totally stubby areaLSA types 1, 2 area-scoped, default summary, no type 3, 4, 5 LSA types allowed

      Auto-cost Reference Bandwidth

      When you set the auto-cost reference bandwidth, Cumulus Linux dynamically calculates the OSPF interface cost to support higher speed links. The default value is 100000 for 100Gbps link speed. The cost of interfaces with link speeds lower than 100Gbps is higher.

      To avoid routing loops, set the bandwidth to a consistent value across all OSPF routers.

      The following example commands configure the auto-cost reference bandwidth for 90Gbps link speed:

      cumulus@switch:~$ net add ospf6 auto-cost reference-bandwidth 90000
      cumulus@switch:~$ net pending
      cumulus@switch:~$ net commit
      
      cumulus@switch:~$ sudo vtysh
      
      switch# configure terminal
      switch(config)# router ospf6
      switch(config-ospf6)# auto-cost reference-bandwidth 90000
      switch(config-ospf6)# end
      switch# write memory
      switch# exit
      cumulus@switch:~$
      

      The NCLU and vtysh commands save the configuration in the /etc/frr/frr.conf file. For example:

      ...
      router ospf6
       ospf6 router-id 10.10.10.1
       interface lo area 0.0.0.0
       interface swp51 area 0.0.0.0
       auto-cost reference-bandwidth 90000
      ...
      

      Administrative Distance

      Cumulus Linux uses the administrative distance to choose which routing protocol to use when two different protocols provide route information for the same destination. The smaller the distance, the more reliable the protocol. For example, if the switch receives a route from OSPFv3 with an administrative distance of 110 and the same route from BGP with an administrative distance of 100, the switch chooses BGP.

      Cumulus Linux provides several commands to change the administrative distance for OSPF routes. The default value is 110.

      This example command sets the distance for an entire group of routes:

      cumulus@switch:~$ net add ospf6 distance 254
      cumulus@switch:~$ net pending
      cumulus@switch:~$ net commit
      

      This example command changes the OSPF administrative distance to 150 for internal routes and 220 for external routes:

      cumulus@switch:~$ net add ospf6 distance ospf6 intra-area 150 inter-area 150 external 220
      cumulus@switch:~$ net pending
      cumulus@switch:~$ net commit
      

      This example command changes the OSPF administrative distance to 150 for internal routes to a subnet or network inside the same area as the router:

      cumulus@switch:~$ net add ospf6 distance ospf6 intra-area 150
      cumulus@switch:~$ net pending
      cumulus@switch:~$ net commit
      

      This example command changes the OSPF administrative distance to 150 for internal routes to a subnet in an area of which the router is not a part:

      cumulus@switch:~$ net add ospf6 distance ospf6 inter-area 150
      cumulus@switch:~$ net pending
      cumulus@switch:~$ net commit
      

      This example command sets the distance for an entire group of routes, rather than a specific route.

      cumulus@switch:~$ sudo vtysh
      
      switch# configure terminal
      switch(config)# router ospf6
      switch(config-ospf6)# distance 254
      switch(config-ospf6)# end
      switch# write memory
      switch# exit
      cumulus@switch:~$
      

      This example command changes the OSPF administrative distance to 150 for internal routes and 220 for external routes:

      cumulus@switch:~$ sudo vtysh
      
      switch# configure terminal
      switch(config)# router ospf6
      switch(config-ospf6)# distance ospf6 intra-area 150 inter-area 150 external 220
      switch(config-ospf6)# end
      switch# write memory
      switch# exit
      cumulus@switch:~$
      

      This example command changes the OSPF administrative distance to 150 for internal routes to a subnet or network inside the same area as the router:

      cumulus@switch:~$ sudo vtysh
      
      switch# configure terminal
      switch(config)# router ospf6
      switch(config-ospf6)# distance ospf6 intra-area 150
      switch(config-ospf6)# end
      switch# write memory
      switch# exit
      cumulus@switch:~$
      

      This example command changes the OSPF administrative distance to 150 for internal routes to a subnet in an area of which the router is not a part:

      cumulus@switch:~$ sudo vtysh
      
      switch# configure terminal
      switch(config)# router ospf6
      switch(config-ospf6)# distance ospf6 inter-area 150
      switch(config-ospf6)# end
      switch# write memory
      switch# exit
      cumulus@switch:~$
      

      The NCLU and vtysh commands save the configuration to the /etc/frr/frr.conf file. For example:

      ...
      router ospf6
       ospf6 router-id 10.10.10.1
       interface lo area 0.0.0.0
       distance ospf6 intra-area 150 inter-area 150 external 220
      ...
      

      Troubleshooting

      Cumulus Linux provides several OSPFv3 troubleshooting commands:

      To…
      NCLU Command
      vtysh Command
      Show neighbor statesnet show ospf6 neighborshow ip ospf6 neighbor
      Verify that the LSDB is synchronized across all routers in the networknet show ospf6 databaseshow ip ospf6 database
      Determine why an OSPF route is not being forwarded correctlynet show route ospf6show ip route ospf6
      Show OSPF interfacesnet show ospf6 interfaceshow ip ospf6 interface
      Help visualize the network viewnet show ospf6 spf treeshow ip ospf6 spf tree
      Show information about the OSPFv3 processnet show ospf6show ip ospf6

      The following example shows the net show ospf6 neighbor command output:

      cumulus@leaf01:mgmt:~$ net show ospf6 neighbor
      Neighbor ID     Pri    DeadTime    State/IfState         Duration I/F[State]
      10.10.10.101      1    00:00:34     Full/BDR             00:02:58 swp51[DR]
      

      The following example shows the net show route ospf6 command output:

      cumulus@leaf01:mgmt:~$ net show route ospf6
      RIB entry for ospf6
      ===================
      Codes: K - kernel route, C - connected, S - static, R - RIPng,
             O - OSPFv3, I - IS-IS, B - BGP, N - NHRP, T - Table,
             v - VNC, V - VNC-Direct, A - Babel, D - SHARP, F - PBR,
             f - OpenFabric,
             > - selected route, * - FIB route, q - queued route, r - rejected route
      
      O   2001:db8::a00:100/127 [110/100] is directly connected, swp51, weight 1, 00:00:20
      O   2001:db8::a0a:a01/128 [110/10] is directly connected, lo, weight 1, 00:01:40
      O>* 2001:db8::a0a:a65/128 [110/110] via fe80::4638:39ff:fe00:2, swp51, weight 1, 00:00:15
      

      To capture OSPF packets, run the sudo tcpdump -v -i swp1 ip proto ospf6 command.