Static-to-OSPF Route Redistribution

Question

Is it possible to use redistribution of static-to-ospf in order to create an external OSPF route other than the type E2? Does this process only create a type 5 LSA and can any other LSA types be created with the redistribution command?

EDIT: I am trying to see if it is at all possible to create OSPF LSAs between two routers alone via any Cisco IOS commands without a host machine creating the traffic. If so, which LSAs are possible? The redistribution command is the only method I have come across so far.

Are External Type 1 routes ok, or are you looking for Type3 Network LSAs? What problem are you trying to solve? — Mike Pennington, Jul 26 '12 at 16:17
I updated my question with an edit to convey what I am looking for. — THE DOCTOR, Jul 26 '12 at 18:39

score 2 · Accepted Answer · answered Jul 26 '12 at 17:24

Sure - in addition to redistributing as LSA type 5 E2 routes, you could also have the routes injected as LSA type 5 E1 routes.

router ospf 1
 redistribute static subnets metric-type 1

Also, you could redistribute the routes as type 7 LSAs (within the area) if the area is an NSSA area. Of course these type 7 LSAs will be converted to type 5 by the ABRs

router ospf 1
 area 2 nssa
 redistribute static subnets metric-type 1

So again, YES you can redistribute statics as either:

Type 5 LSA, Type 1

Type 5 LSA, Type 2 (the default)

Type 7 LSA, Type 1

Type 7 LSA, Type 2

score 2 · Answer 2 · answered Jul 27 '12 at 00:04

In response to the edited question:

Hosts don't generate LSAs; routers do!

If you want to see all the types of LSAs (via show ip ospf database) you could do something like the following:

Type 1 LSA - Router LSA - Simple - enable the OSPF process and include at least one interface!

router ospf 1
 network 0.0.0.0 255.255.255.255 area 0

Type 2 LSA - Network LSA - Enable OSPF on a network interface that is multiaccess (most easily - ethernet) (note this command is simply an alternate way of enabling OSPF on an interface as compared to the above)

int fa0/0
 ip ospf 1 area 0

Type 3 LSA - Summary LSA

You'll need a type 1 LSA to cross an area boundary. Imagine R1 and R2 connected via an ethernet link.

R1:

int l0
 ip addr 1.1.1.1 255.255.255.255
 ip ospf 1 area 0

int fa0/0
 ip addr 10.12.1.1 255.255.255.0
 ip ospf 1 area 0

router ospf 1


R2:

int l0
 ip addr 2.2.2.2 255.255.255.255
 ip ospf 1 area 2

int fa0/0
 ip addr 10.12.1.2 255.255.255.0
 ip ospf 1 area 0

router ospf 1

Now sho ip ospf database on R1 - and you'll see the LSA for 2.2.2.2/32 as a Type 3 LSA!

I could go on with the rest of the types, not sure if this is helpful or not.

score 1 · Answer 3 · answered Jul 26 '12 at 15:40

Sorry this is off the top of my head as I don't have any devices near my right now, but I think you can do this with a route map;

router ospf 123
 redistribute static subnets route-map RM-OSPF-REDIST
!
ip prefix-list PF-STATIC-AS-E1 seq 10 permit 192.168.0.0/24
!
ip route 192.168.0.0 0.0.0.255 1.1.1.1 name StaticRoute
!
route-map RM-OSPF-REDIST permit 10
 match ip address prefix-list PF-STATIC-AS-E1
 set metric-type type-1

If your version of IOS supports is (again, off the top of my head, so I can't remember which versions are supporting which features) you can just use;

router ospf 123
 redistribute static subnets metric-type 1

These (I believe) will both be LSA type 5 still.

Static-to-OSPF Route Redistribution

3 Answers3