IOS to NXOS OSPF Configurations

[MARTIN HUERTER]

I am replacing Catalyst IOS switches with Nexus 9K switches. I am attempting to convert the IOS ospf configurations to NXOS ospf configurations (see configurations below). I can't quite figure out how to convert the redistribute static routes into ospf and how to convert the network statements. The documentation is a bit confusing. If someone could tell me how to do it, or provide me documentation on how to do it, I would greatly appreciate it. 

NEXUS NXOS
router ospf 12345
  router-id 10.255.1.105
  default-information originate
  passive-interface default
interface Ethernet1/31
  description to_switch2
  ip address 10.255.5.6/30
  no ip ospf passive-interface
  ip router ospf 12345 area 0.0.0.0
  no shutdown

Catalyst IOS
router ospf 12345
  router-id 10.255.1.105
  redistribute static metric 100 metric-type 1 subnets
  passive-interface default
  no passive-interface
  network 10.0.0.0 0.255.255.255 area 0
  default-information originate
  bfd all-interfaces

[Flavio Miranda]

@MARTIN HUERTER 

 The redistribution is done via route map

You can check here

https://community.cisco.com/t5/switching/redistribute-static-route-on-ospf-nexus-9372tx/td-p/2929618

On the lnk below, search for "Confiiguring Networks in OSPFv2"

https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus9000/sw/6-x/unicast/configuration/guide/l3_cli_nxos/l3_ospf.html#80478

[MARTIN HUERTER]

I believe I was able to get the static route redistribution done with the following syntax. 

ip access-list static-routes
10 permit ip 10.0.0.0 0.255.255.255 any
20 permit ip 192.168.210.0 0.0.0.255 any

route-map static-in-ospf permit 10
 match ip address static-routes
 set metric 100
 set metric-type type-1

router ospf 12345
 redistribute static route-map static-in-ospf

[Flavio Miranda]

Thank you for sharing. This might help others.

[MARTIN HUERTER]

I am confused by the network configuration in NXOS ospf. The documentation says to put my network summarization on the ospf interface, but I already have a /30 ip address on the ospf interface (see diagram below). When I try to put 10.0.0.0/8 on the interfaces it says it overlaps with route entries already in place. This doesn'.t seem to make sense. Does anyone have an example of how they configured it?   

[Giuseppe Larosa]

Hello @MARTIN HUERTER ,

route summarization can only be performed at area border in OSPF multi area and not at interface level ( this is possiible in EIGRP or RIPv2)

so only by putting other L3 interfaces in a different area then 0.0.0.0 you can use commands like area 0.0.0.x range ...

Edit:

passive-interface default is the equivalent of network 10.0.0.0 0.255.255.255 area 0 . if this is your concern

Hope to help

Giuseppe

[MHM Cisco World]

can I see doc. ?

MHM