OSPF type 5 filtering

[phamthecong]

hi folks,

is there any way to filter OSPF type 5 LSA?

please help.

thanks

[frenzeus]

Hi,

Can u be more specific as to what u're trying to achieve?

Configuring an area as a stub will stop Type 4 & 5 LSA from being flooded into that area.

Maybe u could be more specific about your intention?

[phamthecong]

I have a network as below:

R1---R2---R3---R4

Link from R2 to R3 is in Backbone area. Link from R1 to R2 is in normal area, say area 2. Link from R3 to R4 is in normal area, area 2.

R1 has a static route to number of networks and redistribute them to R2. We dont want the redistributed routes to be advertised across the link R2-R3. We dont manage R3 and R4.

is there any way to filter Type 5 LSA from entering backbone area.

thanks

[frenzeus]

I dont think there's a feature in ospf that allows filtering of Type 5 LSA, though there's a feature that allows filtering of Type 3 LSA btw areas.

Usually, to avoid an area from receiving Type 5 LSAs in a certain area, that area would usually be configured as a stub area. As u might already know, type 5 LSAs are flooded throughout the entire OSPF domain, except stubs, TSAs, Totally-NSSAs.

I might be wrong, but i haven't yet found a way to filter type 5 LSAs without configuring an area to be a stub.