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Questions tagged [igp]

For questions about IGPs (Interior Gateway Protocols), which are routing protocols used within an AS (Autonomous System).

1
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1answer
59 views

Does the Router running multi routing protocol progresses received the routes will store into the Forwarding table?

I have a question about the Router running multi routing protocol progresses. if the bellow snapshot R1 have EIGRP and OSPF progresses, if the EIGRP progress received the routes from R3, will it store ...
4
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1answer
65 views

Does one logical router have only one route table?

If a router running several IGP, such as two EIGRP processes, one OSPF: Will all the IGPs processes' acquired routes be stored in the router's one and only route table or more? I mean, two ...
2
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1answer
158 views

Does the iBGP belong IGP?

We know the iBGP in the AS can transmit the BGP data, it running in the AS, is it belong IGP?
5
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2answers
128 views

Hot Potato, algorithm of selecting route in router

I want to understand a "hot potato" principle. Given a router with 5 interfaces. The first interface gets a packet and has to decide to which interface this packet should be forwarded. I think the ...
1
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1answer
64 views

One AS, Multiple Site with different physical location and ISP, different prefix

I am looking to implement few servers at different location with own ASN having prefix of PI resources of /22 going to divide into 2 x /23. I am unaware of what challenges I can face. As the 2 sites ...
3
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3answers
3k views

Why does MPLS need an IGP (like OSPF) in order to work?

I saw a network using MPLS, BGP and OSPF as main network protocols. I understand that BGP was used to exchange traffic with another AS, and OSPF was used as Internal Gateway Protocol. So, why to use ...
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0answers
406 views

Internal BGP routing issue BIRD

I am trying to setup BGP using BIRD and to announce routes learned from eBGP to router 2 through Router1. The routes show up in the routing table of Router2, however I cannot ping any of them.. (From ...
3
votes
2answers
295 views

EIGRP failover - how do i verify it happened?

I have 2 links to a destination and EIGRP was setup. The faster link is the successor and the slower link is the feasible successor. Switch1#show ip eigrp topology 192.168.1.0 EIGRP-IPv4 Topology ...
2
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3answers
174 views

Do I understand IP Routing correctly?

So I'm revising for a Networking exam and struggling to understand IP routing. If I explain how I understand it, could you tell me where I'm right and where I'm wrong? I'd really appreciate it. Here's ...
1
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1answer
56 views

EIGRP delay summarization?

Could you please explain why when sending EIGR updates only delay of incomig interfaces are summarized and delay of outgoing interfaces is not considered. Please see picture below:
2
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1answer
10k views

RIPv2 manual subnet mask configuration?

As I understand Cisco IOS takes subnet mask from interface to which is network connected and put it in RIPv2 updates. Could you advice please if it possible to somehow manualy set subnet mask of ...
5
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3answers
1k views

BGP - how does IGP know the right route?

Let's consider a host A in an autonomous system AS100. Suppose it wants to communicate with host B in another AS, say, AS200. In AS100 there are several routers. Within one AS, the rotuing protocols ...
2
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2answers
483 views

Routing between branches

I have always used eBGP (with private AS numbers) to route between branches and headquarter sites. However, after reading the Cisco CCNP ROUTE Foundation Learning Guide, it states that best practice ...
6
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3answers
12k views

OSPF or iBGP for interior routing protocol?

So the plan is, two core routers each with a eBGP session to one of two ISPs with full routes. Both routers publish their full tables to each other so they can control traffic flow more intelligently ...
22
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4answers
44k views

Why use iBGP inside an Autonomous System, if IGP protocols fulfill the need for internal communication

Can anyone explain why we need iBGP for the routes when we have the IGP protocols (OSPF, RIP) for internal communication within the AS? I have read a lot of articles and books, but I could not find ...