Questions tagged [bgp]
BGP is Border Gateway Protocol, used on the internet both inside of and in between networks.
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Better Enterprise Multihoming
I would like to get some opinions regarding ways in which I can improve a BGP dual-provider, dual-router design. Each provider supplies a /24 public subnet. I will refer to the routers, circuits, ...
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Route servers and looking glasses - what are they?
I've heard the term "route server" and "looking glass" thrown around here. What are they, and why should I care?
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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 ...
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Troubleshooting "Down BGP" connections
Our network experienced a short outage when one of our BGP routes went down for a short time yesterday. Thankfully our connections failed over to our secondary BGP route after a few minutes, and the ...
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In which OSI/TCP-IP model layers do BGP, RIP protocols belong?
We know that in the OSI or TCP-IP model, the higher layer utilizes the services offered by the lower layer. For example, the data link layer uses services offered by the physical layer, network layer ...
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Routing traffic out different links from the same BGP AS
I have two sites, A and B, in BGP AS 65000, and a third site, C, in AS 65001. All three sites have connectivity via carrier MPLS and there is internal connectivity between sites A and B. I am trying ...
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How does multihoming work with ipv6?
What are the differences between multihoming in IPv4 versus IPv6?
Can an enterprise request a provider-independent IPv6 address space from its RIR/LIR which can be advertised to multiple upstream ...
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Is it possible to remotely influence BGP localpref?
A colleague is attempting to implement active/passive internet multihoming. The design entails sending communities (listed below) to the passive provider to lower the local preference at remote ASes ...
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How to choose a BGP router ID when using IPv6 only?
Usually, when using BGP, you can choose (or your device chooses four you) a router ID from one of your assigned public IP addresses.
Now, let's admit you only run IPv6. As the router ID is still a 32 ...
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Use BGP to defend against a DDoS attack originating from remote AS
I have a question regarding BGP and how to achieve this configuration.
My enterprise core router is connected to an ISP (single homed). This router has already exchanged the specific public ip ...
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When is BGP needed?
I have a question about BGP.
When exactly is BGP needed?
I remember reading that BGP is needed for communication between autonomous systems, but is this always true?
For example, in packet tracer I ...
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BGP multipath with different ASNs feasible for production networks?
on Cisco (this command is hidden for some reason)
#bgp bestpath as-path multipath-relax
The default BGP behavior only installs only routes with exact the same AS_PATH into RIB. With multipath-relax, ...
- 1,281
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How to filter non-bogon prefixes received via BGP from an Internet Exchange(IXP)?
When connected to an Internet peering exchange(IXP), what is a good way to make sure that people don't send you prefixes that they shouldn't be announcing?
With regards to bogons I'm aware of the ...
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Why does BGP RR only reflect the best path?
Can anyone answer why does BGP RR only reflect the best path?
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Why BGP implements its own keepalive instead of using tcp keepalive?
BGP doesn't use TCP keepalive, it uses its own keepalive mechanism. My question is why can't bgp turn-on the SO_KEEPaLIVE of TCP and live happily? why does it not use tcp keepalive and implement its ...
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