Yeah, in this case the sub-area 0.1.1's topology would be hidden from the 0.1's routers and vice versa.
(moreobver, VL can't be used with CISCO's at all because CISCO don't allow to control router-id directly and you can't build VL withouth
Well, you do know that you can create loopback interfaces and the router-ID will be the highest one among them. Say you do:
int lo 0 ip address 255.1.1.1 Hmm. Try yourself. Then, the quote from my config: ! interface Loopback98 description Router-ID ip address 223.255.254.118 255.255.255.255
I even proposed to declare 223.255/16 as private block -:). Looks like doing the sex on the top of the tree - to make the life more complex...
router ospf 111 router-id 1.2.3.4
Actually there is a DDTS on the wish-list, but it is still not implemented for some reason, let's hope it will be.... I can imagine the ONLY reason for such SIMPLE thing... And it's in TODO for a years - now everyone know the trick you showed above...
network and name his _AREA 1.2.3.4_ with the strict filtering on the border.
I was thinking about it as well. One could configure some area range as a "discard" one, effectively saying that all routes dropping into the range should be ignored instead of announced in a summary-LSA. I am not sure if it's the same what I was saying, but approx. it is. We need good inter-area routing with the distribute-control over it. We can control exported prefixes by -STUB AREA- definition and/or summarisations, but we can't control incoming routes,
Btw, do you know _GATED_? It allow to control IMPORTED routes, but for OSPF_ASE_ routes only. I don't think it's possible to control route import anywhere except area borders (for the OSPF case), but why don't do it on the area boundaries?
This is reason why ISP don't like OSPF and such protocols - they can be used for the inter-router routing, but they can't be used to connect with the customers (no, I can run 10 different OSPF processes and re-advertise routes - one more headache for the network admins).
Actually, you can use NSSA, but doesn't allow for filtering either. Sorry, what's NSSA?
PS. From ISP's point of view. What I'd like.
[snip: got your wish, Alex]
3) Moreover, why can't I determine different BGP AS numbers for the boths ISP and CUST OSPF zones.
who said you can't ? or I'm missing something? Yes, I can. But no one (except me) know about it -:).
I mean some mixturing of OSPF and BGP properties. They are mixtured already - OSPF tag can hold 1 BGP paths. Through I don't think it's important for now.
Alex.
On Thu, 27 May 1999, Alex Zinin wrote:
Date: Thu, 27 May 1999 19:36:13 +0400 From: Alex Zinin <zinin@amt.ru> To: nanog@merit.edu Subject: OSPF multi-level hierarchy: Necessary at all?
Hello,
We're currently discussing necessity of multi-level hierarchy in OSPF on the WG mail list.
The idea is to implement SPF-based interarea routing with more than two levels of topology abstraction and route aggregation (we have two levels in OSPF at the moment level1 being intra-area routing and level2 being the inter-area one).
I have some thoughts on how this could be done, but the main question is whether there is a demand for it or not.
Everyone is really welcome to share opinions.
Thanks in advance, ------------------------------------------------------------------ Alex D. Zinin, Consultant CCSI #98966 CCIE #4015 AMT Group / ISL Cisco Systems Gold Certified Partner http://www.amt.ru irc: //EFNET/#cisco, //irc.msn.com/#NetCisco [Ustas]
Aleksei Roudnev, Network Operations Center, Relcom, Moscow (+7 095) 194-19-95 (Network Operations Center Hot Line),(+7 095) 230-41-41,
N 13729 (pager)
(+7 095) 196-72-12 (Support), (+7 095) 194-33-28 (Fax)
------------------------------------------------------------------ Alex D. Zinin, Consultant CCSI #98966 CCIE #4015 AMT Group / ISL Cisco Systems Gold Certified Partner http://www.amt.ru irc: //EFNET/#cisco, //irc.msn.com/#NetCisco [Ustas]
Aleksei Roudnev, Network Operations Center, Relcom, Moscow (+7 095) 194-19-95 (Network Operations Center Hot Line),(+7 095) 230-41-41, N 13729 (pager) (+7 095) 196-72-12 (Support), (+7 095) 194-33-28 (Fax)