Questions tagged [bgp]

BGP is Border Gateway Protocol, used on the internet both inside of and in between networks.

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Brocade L2VPN Route Reflector

I am trying to create an MPLS VPLS network where the VPLS instances are auto-discovered via BGP L2VPN. The issue I'm currently facing is that the routes are not reflected and there seems to be no ...
metrotyranno's user avatar
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How can I tell which prefixes are being advertised?

Forgive me if this is a dumb question but I'm relatively new to the carrier networking world. We own a block of IP addresses, say a /18 and we advertise various /20s, /24s, /23s, etc all over the ...
NOCWarrior093's user avatar
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BGP Route Reflector

In the following configuration, INTERNAL1 and INTERNAL4 are RR and INTERNAL2 and INTERNAL3 are clients. I am not able to see the routes 20.1.1.0 and 10.1.1.0 on INTERNAL3 and 30.1.1.0 and 40.1.1.0 on ...
MUSR's user avatar
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In Bgp TTL security all control packets will have configured hop value?

Topology: loop(2.1.1.1) - routerA (192.168.1.2)--------- (192.168.1.1) routerB - loop(1.1.1.1) I have eBGP peering configured with a Multihop of 2 on both sides and static routes to reach loopbacks. ...
Maradana Kumar's user avatar
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isis redistribute bgp not working

I am having trouble getting route redistribution into ISIS working. It works from ISIS to BGP, but I can't get the opposite to show up. I am using IOS-XR Network has 3 routers: A----B----C A and B ...
Colin Z's user avatar
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Extract upstream/downstream ASNs from BGP table path

I want to extract upstream and downstream ASN for any given ASN, for example: https://www.cidr-report.org/cgi-bin/as-report?as=AS4826&view=2.0 My goal at the end is to generate ASN route graphic ...
Yoan Arnaudov's user avatar
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eBGP failover without packet drops

I have core1 and core2 router peer with same ISP but distinct hardware and they are sending us default route. currently all in/out traffic going over to core1 and core2 is idle (standby), I have iBGP ...
Satish's user avatar
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Get ASN Upstreams/Downstreams/Peers

I'm trying to gather the Upstreams/Downstreams/Peers of an ASN. Lets take for example AS8866, I run this query on the ripe API https://stat.ripe.net/data/asn-neighbours/data.json?resource=AS8866 ...
Yoan Arnaudov's user avatar
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Routing daemon vs router configuration

Which is the difference between a routing daemon and a router configuration? For example using BIRD you can set up a BPG session, but you can always set up a BGP session for example using a CISCO ...
FbaStack's user avatar
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Active\Passive Routers w\ BGP

What I'm trying to do is take two routers, "A" and "B" where 'A' is the primary router. Just like with active\passive firewalls and HSRP I want to "float" the default gateway between either Router A ...
SchoolNet809's user avatar
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Can BGP-LS provide an ip address as a node attribute when distributing IS-IS

I have an IS-IS network (all cisco) with a BGP router (cisco) that I am using to distribute the network link-state for monitoring / analysis. one thing I would like is to receive an IP address for ...
Colin Z's user avatar
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Junos: how to change BGP MED for secondary node?

I have vSRX cluster, which announce some protected addresses over IBGP. Each node has two sessions with two routers. (I use ge-0/0/1 and ge-7/0/1 for that). I found that if fail-over happens, and ...
George Shuklin's user avatar
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Why isn't iBGP peer announcing external route it learned to its only peer?

I'm using VyOS to create a BGP lab. It has 6 routers, each in an iBGP pair, and 3 autonomous systems. Routers 1 & 2 - AS1111 Routers 3 & 4 - AS2222 Routers 5 & 6 - AS3333 All routers are ...
3rett's user avatar
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Differences between BGP(routing protocols) and vpn mpls?

I am new to networking, so bear with me, 1-I wanted to clear my query: why do we need BGP or any routing protocols if we have vpn or wan technologies like mpls ? 2-Can't we just run bgp between two ...
user64956's user avatar
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Is it possible to determine the origin of a BGP withdraw message?

is it possible for an ASN in the BGP path to determine what ASN has been the originator and the cause of withdraw message?
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Why doesn't BGP come up when no hold-time is defined? [closed]

Why doesn't BGP come up when no hold-time is defined? if defined, the BGP protocol comes up without any problem.
Bulki's user avatar
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Unexpected bytes in AS_PATH BGP attribute

I am parsing out the ASNs from several AS_PATHS. A majority of the attributes I encounter look like this one: [64, 1, 1, 0, 64, 2, 10, 2, 2, 0, 0, 23, 169, 0, 0, 50, 156, 64, 3, 4, 200, 40, 162, 202]...
RJ Rybarczyk's user avatar
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How is the MD5 hash calculated in BGP?

The RFC is very superficial on the implementation details. What is the injective function being used? https://www.rfc-editor.org/rfc/rfc2385 MD5 digest is produced by applying the MD5 algorithm to ...
Anon1888's user avatar
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Difference between step 3 and step 5 of BGP route selection process?

Step 3: Locally injected routes (Locally injected is better than iBGP/ eBGP learned) Step 5: Origin Prefer I over E. Prefer E over ? I went through lot of articles on the internet but not able ...
unknown29's user avatar
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Traveling Salesman Problem (TSP) applied to network routing protocols? [closed]

Is this very common for larger enterprises that have many thousands of servers to use something like ant colony or similar algorithms to work together with network routing protocols like BGP to solve ...
Tagar's user avatar
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EIGRP to BGP to EIGRP

I would like to ask if it is possible to implement eigrp routing sent through bgp? I wanted to route from PC-1 to PC-2 using EIGRP. The connection between all of the three routers are through BGP ...
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Internet Scale Routing Table Size

In the link below, it is said that there are near one million prefixes for IPv4. https://bgp.he.net/report/netstats I want to know that it is a must for ISP routers to cache all these million IPv4 ...
A.A's user avatar
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Single-homed connection to ISP without NAT feature

Is it possible to connect my private network to the ISP router without a Network Address Translator (NAT) feature enabled on my router? As I understand, in a single-homed scenario connection to ISP, ...
A.A's user avatar
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Is there a way to check which routes are matched by a term in a routing map?

I have created a prefix-list and I am using it in a route-map. However, my route-map is not working as I expect it to work. ip prefix-list LIST_A seq 5 permit 10.20.20.0/22 ge 32 route-map A-B-OUT ...
monica's user avatar
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How to read a BGP table?

I have come across BGP looking glass where I can see the routing table for public routers. Please find below a public entry: BGP routing table entry for 78.97.0.0/16 Versions: Process ...
Darkov's user avatar
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BGP rule to avoid given ISP?

Is it possible to have a rule/policy in BGP to avoid a given ISP for the traffic? Ex.: traffic from the USA should touch middle east ISPs if the target/source is not from/to there. I am not sure ...
HolcombSimons's user avatar
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What are the current security issues S-BGP has?

The question is explained in full in the title. I wish to know what the security issues are when deploying S-BGP. Thank you in advance!
IliasWhoElse's user avatar
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What does the BGP protocol consider when determining the best path?

What does BGP protocol consider when determining the best path? Why is it considered the slower than interior routing protocols like RIP, OSPF, etc?
Rumesh Madhusanka's user avatar
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BGP best path algorithm throttling?

Let's consider a simple scenario: Router R1 in AS100, which has direct connections to routers R2 (AS200), R3 (AS300), R4 (AS400), R5 (AS500). Regular eBGP neighborships are formed over these links. ...
mkurek's user avatar
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How is traffic correctly routed in Site-to-Site VPNs where all sites are on the same subnet?

http://rockhoppervpn.sourceforge.net/ref_site2site_bridge_6.html The diagram on this page shows all 3 sites using the same subnet, 192.168.0.0/24. Let's say on the hub site where 192.168.0.10 is the ...
Lewis Kelsey's user avatar
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166 views

How TCP connections between origin and node servers over a BGP Anycast gets established?

Server A and B have the same IP address with anycast. Server B connects to the origin server that is very close to server A and very far away from server B, since server A is closer, the response will ...
Amin Vakil's user avatar
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Problem in cisco routing bgp routes

We have an outbound route-map on an eBGP peer that adds some communities to certain prefixes. Is there any way to prove that this is actually happening from the sender side in classic IOS? show ip ...
rohinth's user avatar
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BGP Collector and Vantage Point relationship

I am currently reading a paper BGPStream: A Software Framework for Live and Historical BGP Data Analysis where authors say: Normally, a BGP session with a collector is configured as a customer-...
bdskfsdk321dsad3's user avatar
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Same /24 IP prefix, same AS for 2 different locations, possible?

Let's say I have 2 locations: 1. the United States Datacenter 2. the Russian Federation Datacenter I have 1 /24 Subnet with 1 AS. Both sites have a different ISP. My target is to: allocate /24 for ...
dnleiman's user avatar
3 votes
3 answers
799 views

BGP and NAT Not working

I have an odd issue with BGP+NAT. I have 2 separate routers and 2 different ISP's. Topology looks like this: ISP1--BGP--> RTR1 \ \--OSPF-- Palo Alto Firewall-- Internal ...
Network Samurai's user avatar
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1 answer
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BGP local-as command clarification

On my network infrastructure, an Arista switch is the core switch and a pfsense server the gateway. BGP is used to advertise routes for all the internal networks. On Arista switch, I see the BGP ...
xrpapak's user avatar
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How does the BGP UPDATE message propagation work?

I am currently reading about Routing around Congestion Defense and the non feasibility of this approach. Since to use this method a lot of BGP poisoning would be necessary and to switch paths several ...
baxbear's user avatar
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Route advertisement and FIB programming

Que1. Assuming bgp is running on a network device, will the route advertisement and FIB programming(basically populating entries in hardware) occur in parallel? Or does it occur sequentially, meaning, ...
fsociety's user avatar
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High Throughput on BGP Multihomed Network

I've One site connected to my server location via BGP over MPLS and at my server location 2 edge routers cater these WAN links, and are further connected to Servers via switches. Now, Is it possible ...
danish's user avatar
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5 votes
2 answers
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What is the difference between connect and active states of BGP?

What is the significance of having two different states in FSM when both try to establish TCP Connection?
unknown29's user avatar
4 votes
2 answers
142 views

What does a transition from static IP to BGP look like?

We initially got a /30 from our upstream and now we're ready to start running BGP to advertise our own /24. What does that sort of process typically look like? Does it likely require some prior ...
Matt's user avatar
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How does aggregate routes behave in BGP?

If a router received two BGP updates for the same prefix and both these updates are aggregate paths how do the router decide which one to take? Let us say that it needs to decide based on AS Path ...
kaki no's user avatar
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2 answers
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How BGP guarantees same route for a forwarded packet?

In BGP all routers choose the best route to a single destination. So for Router A and destination D, A will forward the packet to the next-hop router (let us say router R) after knowing the best route ...
kaki no's user avatar
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2 votes
2 answers
744 views

Troubleshooting connectivity in BGP/Quagga/Docker lab

I have created a virtual networking lab to test BGP routing. The lab is made up of two Debian Docker images which serve as end users and two images running Alpine Linux with Quagga to serve as the ...
banana muffin's user avatar
1 vote
1 answer
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Ho to implement RPKI for our Network

I would want to implement RPKI in my network. I have gone through some documents by which i cant understand the implementation process. What are the steps i should follow to implement RPKI in my ...
user62194's user avatar
3 votes
1 answer
177 views

How to bypass when network speed over a special number in Juniper?

I have a requirement, such as I have 113.100.15.0/24 segment IP addresses. in Juniper M480 Router I connected to BGP-A(1G) and BGP-B(10G), by default the 113.100.15.0/24 out the Router it go ...
244boy's user avatar
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Why do IXPs need ASN?

Does anybody know why an IXP needs to have an ASN? Will that ASN appear in the AS-PATHs or will it be transparent?
konstantinosAR's user avatar
2 votes
2 answers
198 views

Method to rename the existing BGP peer group

In Cisco ASR router, do we have any method to rename the existing peer group without removing and recreating it?
Blake's user avatar
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1 answer
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Reasons for buying ASN for organisation that are located at single place

I see here that even some organisation/universities have bought ASN which are located at single location. What benefit they will get by buying ASN ? Is it compulsory to buy ASN if I have to buy some ...
Number945's user avatar
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What is benefit of allocating ASN to edge routers and not Ip addresses

What is benefit of allocating ASN to edge routers and not Ip addresses ? I mean we could have given these edge routers unique public ip addresses too ?
Number945's user avatar
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