Restrictions and Basic config

Restrictions:

• Unlike in XE, in XR we need ospfv2 for IPv4 and ospfv3 for IPv6. Also Ospfv2(in XR) cannot form neighborship with ospfv3(ipv4 in XE/IOS)
• OSPF stub routing on XRv (virtual) does not work
• OSPFv3 IPv4 nssa does not work in XE/ IOS. Use ospfv2 for ipv4 nssa
• For Stub routing to work on any one router to work, that router must have atleast one interface in area0 i.e. connected to backbone area (Hint: Use loopbacks)
• When configuring passive interface using OPSFv3 in IOS/ XE, network prefixes unlike in XR by default won't get advertised with LSA, on top of that we don't have specific command to advertise passive interface in OSPFv3 for IOS and XE. We can use tools like redistribute connected with route-maps.

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Configurations IPv4

IOS/XE

router ospf 200
 router-id 200.0.0.23
 network 0.0.0.0 0.0.0.0 area 0

OR

router ospf 200
 router-id 200.0.0.23
!
interface Ethernet0/0
 ip ospf network point-to-point
 ip ospf 200 area 0
!

OR

router ospfv3 10
 router-id 2.2.2.2
 !
 address-family ipv4 unicast
  passive-interface Loopback0
 exit-address-family
 !
 address-family ipv6 unicast
  passive-interface Loopback0
 exit-address-family
!
interface GigabitEthernet3
 ospfv3 10 network point-to-point
 ospfv3 10 ipv4 area 0
 ospfv3 10 ipv6 area 0
!
interface GigabitEthernet4
 ospfv3 10 network point-to-point
 ospfv3 10 ipv4 area 0
 ospfv3 10 ipv6 area 0
!

XRv

router ospf 10
 log adjacency changes
 router-id 6.6.6.6
 area 0
  interface Loopback0
   passive enable
  !
  interface GigabitEthernet0/0/0/0
   network point-to-point
  !
  interface GigabitEthernet0/0/0/2
   network point-to-point
  !
 !
!

Configurations IPv6

IOS/XE

ipv6 router ospf 200
 router-id 200.0.0.23
!
interface Ethernet0/0
 ipv6 ospf 200 area 0
 ipv6 ospf network point-to-point
!

OR

router ospfv3 10
 router-id 2.2.2.2
 !
 address-family ipv4 unicast
  passive-interface Loopback0
 exit-address-family
 !
 address-family ipv6 unicast
  passive-interface Loopback0
 exit-address-family
!
interface GigabitEthernet3
 ospfv3 10 network point-to-point
 ospfv3 10 ipv4 area 0
 ospfv3 10 ipv6 area 0
!
interface GigabitEthernet4
 ospfv3 10 network point-to-point
 ospfv3 10 ipv4 area 0
 ospfv3 10 ipv6 area 0
!

router ospfv3 10
 router-id 6.6.6.6
 log adjacency changes
 area 0
  interface Loopback0
   passive
  !
  interface GigabitEthernet0/0/0/0
   network point-to-point
  !
  interface GigabitEthernet0/0/0/2
   network point-to-point
  !
 !
!