Questions tagged [bgp]
BGP is Border Gateway Protocol, used on the internet both inside of and in between networks.
693 questions
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OSI Model - Is this statement accurate?
Found this statement in the "The Art of Network Architecture" book, but I can't understand it, as I don't see why routing protocols in the OSI model run on Layer 2 (data link), as the book ...
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FRR BGP peering on ipv6 link-local address
I have following setup in my lab. Host1/2 running ubuntu with FRR daemon for BGP. R1 is my cisco nexus switch. I want to route traffic between host1 to host2.
[host1]------ibgp----[R1]------ibgp----[...
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how does anycast network deployment work?
as far as i understand, anycast network i.e a /24 block is announced by a BGP with the same ASN from multiple regions. anycast networks such as 1.1.1.1 and 1.0.0.1 are largely used for DNS services or ...
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Are multiple BGP-LS NLRIs in a single MP_REACH_NLRI path attribute permitted?
I have a network capture of a real-life BGP-LS session:
...
Path attributes
Path Attribute - ORIGIN: IGP
Path Attribute - AS_PATH: empty
Path Attribute - LOCAL_PREF: 100
Path Attribute ...
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VPLS signaling choices. BGP or LDP?
There are two kinds of BGP signaling (there are more, but I need to compare these two):
1- Both signaling and auto-discovery with BGP
2- LDP signaling and BGP auto-discovery
When I look at both ...
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BGP between peers that are 1 hop away?
I was wondering the need for a static route in the example below where its from AS65100 directly to AS65200 - 1 hop away. A BGP is established, so would there be a need/requirement for a Static Route ...
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When does accepting a more-specific prefix for the IXP LAN cause a black hole for connectivity to the IXP LAN?
RFC 7454("BGP Operations and Security") says:
When a network is present on an IXP and peers with other IXP members
over a common subnet (IXP LAN prefix), it SHOULD NOT accept more-
specific ...
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change routes to a network on a Cisco router depending on which source loopback you use without using PBR or VRF?
in a Cisco environment , can you change routes to a network 1.1.1.1 on a Cisco router depending on which source loopback you use on that router without using PBR (Policy Based Routing ) ?
so if i ...
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Direct Peer IP, Next Hop Latency is Different based on the destination [closed]
I’m experiencing a network issue with one of my BGP peers, and I need some help understanding the root cause.
Notes: Public IPs i provided is random just to describe the issue
I have a BGP peer for ...
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Wireshark BGP Decoding
I have a question about how Wireshark decode MP_REACH_NLRI BGP-attribute witj AFI = 1 and SAFI = 128. On the screenshot prefix length is 118 bits. We have 24 bits for one MPLS label and 64 bits for ...
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Help understanding a use case to develop a network topology
I am self learning networking and now want to create a simple network topology in containerlab. This is only for a simple test lab. For this I am only using OSPF and BGP. I have came up with a ...
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Deny default route to BGP peer
I've a situation where i want to stop the default route(0.0.0.0/0) from sending out to a specific BGP peer.(EBGP peering)
I was working on Juniper EX-series
Example:
B(AS 2) is connected to A(AS 1) ...
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Must an autonomous system be internally fully connected?
Must every part of an autonomous system be connected inside the system to every other part, or can it be split in two (or more) distinct parts which are only connected through other autonomous systems?...
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BGP - How are loops avoided when they are not caused by an AS_PATH cycle?
The standard answer I am seeing for how eBGP avoids routing loops is that eBGP routers of an AS will check each AS_PATH that is advertised to them and will discard the path if it contains their own AS ...
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How to check the validity of a BGP prefix?
Let's say, that an organization has two geographically diverse DFZ sites named site-A and site-B. In site-A, the network 192.0.2.0/24 is in use and in site-B the network 198.51.100.0/24 is used. ...
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