OSPF prefix-suppression work with NSSA Type-7 and translated Type-5?

[m1xed0s]

Say I have two ospf routers in Area 100: R1&R2 and the area is configured as NSSA. R1 also connects to the Area 0 which makes it as the ABR between Area 0 and Area 100. Within NSSA, I have some static routes redistributed into OSPF on R2. These redistributed routes are showing up as N2 in Area 100 and E2 in Area 0.

But if I go under OSPF process and enable

prefix-suppression

on the ABR, then those redistributed routes will be disappeared from Area 0 (still shown as N2 in the Area 100)... Why does ABR suppress the translated Type-7 into Area 0? High-level diagram is attached.

According to cisco documents, link below, Prefixes that are associated with loopbacks, secondary IP addresses, and passive interfaces are excluded because typical network designs require those to remain reachable. and 

OSPF prefix-suppression

helps in faster Shortest Path First (SPF) calculation due to less number of prefixes in the database (DB). OSPF Type 3, Type 4, Type 5, or Type 7 LSAs are not suppressed.

https://www.cisco.com/c/en/us/td/docs/ios-xml/ios/iproute_ospf/configuration/15-mt/iro-15-mt-book/iro-ex-lsa.html

https://www.cisco.com/c/en/us/support/docs/ip/open-shortest-path-first-ospf/213404-open-shortest-path-first-prefix-suppress.html

Any idea?

[MHM Cisco World]

I dont full get design here,
but share topology first.
second I think one router is act as ASBR & ABR this make it inject route as LSA5 "E2"
where the other router act as ASBR this make it inject route as LSA7"N2"

[m1xed0s]

Diagram added in the post.

I have

prefix-suppression

enabled on all the routers. But from Cisco doc, LSA7 and 5 should not be suppressed anyway...unless, the LSA5 referenced in doc excluding translated LSA5...

[MHM Cisco World]

I will run fast small lab and see result

[m1xed0s]

If I disable suppression for the link between R1 and R2, while keep globe suppression, it would work. Maybe my issue is because the doc is not clear?

[MHM Cisco World]

one more think is it NSSA or T-NSSA ?

[m1xed0s]

Totally NSSA. I don’t need regular LSA5 coming in. 

[MHM Cisco World]

I make the Area T-NSSA and I redistribute the static route,
are static route toward Null0?

[m1xed0s]

nope. I have another router behind R2. But the same result for redistributed connected such as Loopback.

[MHM Cisco World]

Yes I do lab and under analysis,
when

prefix-suppression

config in AREA 1 "NSSA area"
any static route redistribute there is log message that P-bit is clear, 
P-bit meaning that this prefix will never translate from LSA7->LSA5.
so I will analysis this behave.

[MHM Cisco World]

so after analysis it fast
config LO in R2

not prefix-suppression

and you can see prefix now where it allow to translate now from LSA7->LSA5
Why?
other router need advertise router IP to routing packet toward ASBR of NSSA.

[m1xed0s]

What lab device you use for testing? Possible it is issue on lab images.

[MHM Cisco World]

I run it in GNS3 and success.
 

[MHM Cisco World]

[m1xed0s]

So you didn’t run into the issue I have? If so, what device image you used for testing?