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Questions tagged [bgp]

Border Gateway Protocol (BGP) is the protocol which makes core routing decisions on the Internet.

Border Gateway Protocol (BGP) is the protocol which makes core routing decisions on the Internet. It maintains a table of IP networks or "prefixes" which designate network reach-ability among autonomous systems (AS).

It is a path vector protocol, or a variant of a Distance-vector routing protocol. BGP does not use traditional Interior Gateway Protocol (IGP) metrics, but makes routing decisions based on path, network policies and/or rule-sets. For this reason, it is more appropriately termed a reach-ability protocol rather than routing protocol.

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Is there a way to test alternate IPv4 routes?

i am using Hurricane Electric's Tunnel Broker service to get IPv6 connectivity. TunnelBroker lets you have access to the IPv6 Internet by using a standard IPv6 tunneling protocol. You send IPv6 packets, wrapped inside IPv4 packets, to one of their…
Ian Boyd
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What do "BGP graphs" show (e.g. Hurricane Electric (HE))?

Title says it: I am wondering what "BGP graphs" (e.g. the ones on Hurricane Electric or robtex) show exactly? Another example can be found here on superuser: Is there a way to test alternate IPv4 routes? I would expect the websites to explain it…
scherand
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Packet Drop When BGP Withdrawal

We are announcing our prefix to ISP A and ISP B via BGP, 1.0.0.0/23 to ISP A, and 1.0.0.0/24 and 10.0.1.0/24 to ISP B. What we want is that when we withdraw 1.0.0.0/24 from ISP B, communication for 1.0.0.0/24 switches to ISP A seamlessly. (Because…
minjunkaaang
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How can different IPs in one subnet have different routes?

Some days ago I've stuck into the situation of unavailability for my work VPN. As I was at work, I've tried to ping my home server, and it didn't respond; OK, too many options for that to happen. But then I've tried to connect to it from my phone…
Victor Nikityuk
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Buy IP range independent of provider

I would like to ask a question. Is there any wat to acquire IP, independent of provider? Can I buy IPs and use them in different data centers? We have physical servers in the united states and germany. Is it possible to buy IPs and use them in…
Rafael Arcanjo
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Attempting to use Ubuntu 18.04 IP forwarding, but it will not forwarding packets received over GRE tunnel

I have two servers, server A and server B. Traffic for a certain subnet, 192.168.1.0/24, comes in through server A. Server A has a GRE tunnel setup with server B, and routes all traffic received for 192.168.1.0/24 over the GRE tunnel to server…
Timothy White
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Where does ARIN publish IP to ASN assignments?

If ARIN (https://www.arin.net) is in charge of assigning IP addresses to individuals and organizations (in America) in order to avoid IP address conflicts on the internet, why do they not publish an Autonomous System Number (ASN) that the IP address…
user1748155
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How are ICANN's IP address reservations enforced?

I've read that ICANN is the authority dedicated to assigning IP addresses to individual entities, so that no two separate entities are using the same IP address on the internet. It is my understanding that when assigning an IP address, an autonomous…
user1748155
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Junos - Shortening internet full bgp table

I want to shorten internet full bgp table (450K records) in such a way to catch all prefixes from /0 to /21 as well as all prefixes of /22 or more which are not included within /0 - /21 prefix range. Example…
reuf
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What prevents an as from announcing false ip addresses?

In BGP an AS could announce paths for arbitrary IP addresses, resulting in false routings. Is there a mechanism that prevents such actions?
timtam
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change route according to gateway from DHCP

I have configured BGP on my router (using Entware) to send some routes through VPN. It's worked. But now I needed exclude one deivce from it (it must go not via VPN tunnel). My bird config log syslog all; log stderr all; router id x.x.x.x;…
zikasak
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Is my 6to4 relay node Hurricane Electric?

I enabled 6to4. On bgp.he.net I see: You are visiting from 2002:5aXX:XXXX:X:XXXX:XXXX:XXXX:XXXX Announced as 2002::/16 (6to4) Announced as 2002::/16 (6to4) Announced as 2002::/16 (6to4) Announced as 2002::/16 (6to4) Announced as 2002::/16…
MCCCS
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Why my routing preferred over far away upstream provider than local upstream?

Here's a good example: I have a server located in my country, and I purchased from two upstream/transit providers to route my traffic to the world. Upstream A is located in far away region, and Upstream B is located in my country. So I setup…
liyan
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Route Public IP with GRE Tunnel with BGP/BIRD from a VPS to my Cisco at Home

I want to learn how to do this. I Will try to explain as better. - First: I own a IP Block from RIPE - Second: I have vultr.com VPS service and they are announcing my /24 and I can get the public IPs on the VPS with BIRD and dummy*…
Alvaro Vidal
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Redundant VPN connection to AWS using one physical router

I am trying to make the VPN connection redundant as described in this article. https://docs.aws.amazon.com/vpn/latest/s2svpn/VPNConnections.html What I want to achive is, setup two customer gateways(CGW) for each internet connection and if one…
Junichi
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