Questions tagged [bgp]
BGP is Border Gateway Protocol, used on the internet both inside of and in between networks.
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Juniper router how to check the BGP process port?
Juniper router how to check the BGP process port?
If I have a router with IP address 12.12.21.1, we know it run a BGP process, which use TCP 179 port as default.
How can I check if port 179 is ...
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How to understand the output below from BGP?
I don't understand some data of the show route:
admin@MX-RE0# run show route 36.250.236.6
inet.0: 736608 destinations, 806660 routes (736608 active, 0 holddown, 7 hidden)
+ = Active Route, - = Last ...
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Can non-recursive BGP route be used to determine next-hop for recursive BGP route?
In BGP recursive scenario, the recursive route is taking an unexpected next-hop. Here is the routing table:
S* 0.0.0.0/0 [10/0] via 10.10.10.1, wan
B 172.16.5.0/24 [20/0] via 172.80.80.1, MPLS, ...
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How to properly setup graceful-shutdown community
I'm trying to setup graceful-shutdown community but it looks I cannot make it working.
community-set comm-graceful-shutdown
65535:0
end-set
!
route-policy SOMEIX-IN
! tried set local-preference 0 ...
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Can two networks with the same subnet be connected to the same router in different VRF?
Let's say I have the following four networks:
Network A: 10.0.1.0/24
Network B: 10.0.0.0/24
Network C: 10.0.1.0/24
Network D: 10.0.0.0/24
I would like to connect networks A and B together, and do ...
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Can I announce prefix 161.117.25.0/24 even though I don't have all of /24 IPs?
I'm managing one BGP router, under the router I'm trying to announce the following IP prefix:161.117.25.0/24. But the problem is that some of the IP addresses were borrowed by other AS(Autonomous ...
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Why does my route-map blackhole some equally specific routes? [closed]
I have a challenging situation. I have two routers, in VIRL, sharing routes via BGP and OSPF I am attempting to remove the "network 0.0.0.0 255.255.255.255 area 0" from my OSPF process. I have tried ...
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Connecting eBGP and iBGP routers in Quagga
I am trying to run intra and inter-domain routing using Quagga. I like to announce a prefix from AS7 and I like AS6 receive it and send it to AS2(as shown in the attached topology).
I know for intra ...
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local pref question
i have a cisco router with 6 bgp peers, 4 bgp peers is from out ip transit's and i am receiving full routing (bgp) table from them. 2 bgp session is over GRE tunnel. and i am receiving 1.1.1.0/24 and ...
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How long the EBGP peer convergence time
We are using Anycast, and I plan to implement the "nearest access" by appending myself AS path to impact my peer BGP routers.
For example I have two POPs(they are same ip), Pop1 in London and POP2 ...
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Understanding RIB and Update data from RouteViews
Can someone walk me through some RIB data from RouteViews? I'm having trouble understanding how to make sense of it. The main thing I need to figure out is what part of the RIB entry can be used to ...
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Explanation of repeated ASN in an AS path from a RouteViews file
From the RouteViews RIB files, I was looking at the snapshot from Nov 06, 2017 at 18:00 UTC. This has to do with this BGP routing misconfiguration -- https://dyn.com/blog/widespread-impact-caused-by-...
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Juniper SR300 maximum BGP routes
I've got a Juniper SRX300 which i'm using to connect to 2 BGP peers. The documentation i've read says this SRX only supports 300,000 BGP routes, so for each peer I created an import policy (based on ...
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VXLAN / EVPN Types
Looking into EVPN and the route types (type 2 and 5) is my understanding correct.
In terms of their placement into the relevant forward tables upon the device.
EVPN Route Type 2: MAC/IP Advertisement
...
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JunOS Use iBGP route over OSPF route
Hello i have an issue where my Juniper router doesnt advertise BGP 10.255.255.4/32 to a neighbor because in inet.0 it is not issued as the best route
root# run show route table inet.0
inet.0: 11 ...
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how to change a BGP path in juniper?
How to change the selected BGP route?
I show the route 43.242.33.39, there shows 3 GBP paths.
but I can not ping the ip(43.242.33.39). and can not traceroute it.
how can I do with this?
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BGP - Advertise VRF routes
I have a router with a Global Routing Table (GRT), and a VRF. My end goal is to advertise to my eBGP neighbor my VRF routes.
I have actually successfully done it by using address-families (ipv4, ...
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EVPN/VXLAN Flood and Learn
With the original VXLAN spec (RFC) there was no control plane.
But Flood and Learn was used via either IR or multicast head-end replication.
EVPN was then introduced as the control plane.
My ...
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BGP Juniper not reflecting to Cisco?
I am really new to working with Junipers and I am struggling a bit with Route Reflector configuration.
I have 3 routers Cisco-Juniper-Juniper2
here is my config:
Cisco:
router bgp 100
neighbor ...
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Regarding ECMP hashing
Assume we have a following topology.
R1 represents Router1, R2 represents Router2, R3 represents Router3 and R4 represents Router4.
Src represents the source Server.
Dest represents the destination.
...
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Propagating 'trash' ASN, what happens?
This sounds crazy, but I'm analyzing the raw RIS BGP announcement dataset and I spot this announcement:
BGP4MP|1543859911|A|198.32.125.181|51185|52.94.20.0/24|51185 9304 1161216244|INCOMPLETE|198....
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How do you specify BGP Authentication Key when using Verizon's Secure Cloud Interconnect? [closed]
I am trying to establish a Direct Connect Link using Verizon's Secure Cloud Interconnect service.
I have established the connection in the Dynamic Network Manager on the Verizon side and the VIFs ...
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In one organization having two ISP which configured on fortigate firewall ? How can we do the failover for internet?
Organisation don't have AS number .As of now we are doing manually route for any ISP at a time.
when default Internet link is go down that time making second link enable on firewall.
I saw the some ...
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3
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How is traffic forwarded though IXPs if route servers do not forward any traffic
while i was studying about IXP route-servers, i read that they do not forward any traffic. I get that a route server is a "control plane" entity and it is used for easier bgp peering. However, i ...
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Setting local preference in BGP
I am trying to set the local preference for this configuration
To make a route from R1 to R4 via R3. That's how i configure R3
R3#conf term
Enter configuration commands, one per line. End with ...
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Download Internet Routing Table
What is the best way to download a snapshot of the Internet's IPv4 routing table? I need check if IP addresses are routable. It needs to function offline, so a looking glass server won't work. I know ...
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Bad mask for loopback interface
I am trying to implement BGP session. I was given this table.
When I try to configure loopbacks the first loopback works in the proper way
R1(config)#interface loopback 0
R1(config-if)#ip
*Mar 1 ...
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JunOS iBGP and return paths odd behaviour
I've got a somewhat basic iBGP configuration with a routing instance "global" between two Juniper vSRX's - each Juniper vSRX has an uplink of its own from a different transit provider with a default ...
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Gather the BGP data by using TCP connection on port 179
In order to gather the information shared between BGP peers, what port number should be used to connect using TCP (I am using 179, and don't see the connection being established)? Will I be able to ...
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Use case for two BGP ASNs?
I’m new to BGP and have a relatively simple question, or so I think it is for you BGP veterans. I would like to build two new seperate edge networks at my company; one for production services and ...
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All routes about a IP in my Router AS-PATH last AS number is Idle
I can not ping the IP 202.137.151.185 from my router.
and in my router I show a IP's route, there gets the following information:
admin@EE-MX-RE1# run show route 202.137.151.185 ...
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Why is the BGP base on TCP 1027 rather than 179?
Why is the BGP foreign address port 1027?
I use BGP to connect Router1 and Router2, but when I show the TCP progress:
Router1>show tcp brief
TCB Local Address Foreign Address ...
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juniper advertising smaller subnets with a bigger static route in BGP
I have a /18 in RIB but I would like advertise smaller subnet in BGPfor specific reason to diff ISP etc. Is there a way to do it without creating a null route or static route. Is some way in policy ...
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Why do we need MPLS when implementing L2/L3 VPNs?
Yes, I know that MPLS doesn't care about L3 and higher levels and it is one of its features. But I do not really understand its role in L2/L3 VPNs.
L2VPN - we are building xconnects to PE's AC. Why ...
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How can I see where BGP is advertising a given prefix? (Junos)
I'm working in a complex BGP environment on Juniper MX480s. We have many peers in various routing instances advertising prefixes to us, and then we advertise a subset of those prefixes to a subset of ...
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Cisco BGP Graceful Restart behavior
In our environment we generally have ASR-1000X-2s everywhere peering via iBGP/eBGP. These routers have no redundant RPs, hence cannot keep forwarding traffic while the router reboots or crashes. As ...
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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?
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Issues with Juniper MX-series iBGP routes
I have a simple setup:
2x Juniper MX-Series routers each having one uplink to a transit provider
iBGP session between both routers (point-to-point)
For testing purposes I've disabled the uplink from ...
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PP BGP Load Balancing with JUNOS
So we've got a couple of BGP upstream providers, whom both are providing us with their full internet routing tables.
What we are now wanting to do, is utilize both providers, rather than just one ...
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How does BGP decide which prefix to advertise out of the prefixes in the routing table? [duplicate]
The ip routing table shows that I have 4 routes to reach 0.0.0.0/0.
#show ip route 0.0.0.0/0
0.0.0.0/0, ubest/mbest: 4/0
*via x.x.16.6, [20/0], 2d, bgp-64500, external, tag 64500
*via x.x.17.4, [20/0]...
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Why use iBGP over eBGP?
Why would you use iBGP over eBGP. i.e why use a single AS with an RR over multiple AS's using eBGP.
Is it simply for peering design simplification i.e large amount of devices all peering to a set of ...
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Config BGP policy for limit ISP path in Juniper MX 480 Router
Now we have a source IP14.135.4.0/24, we are involved in 5 different ISP, such as A, B, C, D, E. Now we want to access 14.135.4.0/24 not through the path of ISP B and ISP D, but through the other ...
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Routing an owned /24 IPv4 block to a single server [closed]
How would one go about routing a recently-purchased /24 block of IPv4's to a single server? The server is colocated in Zare.com, and the BGP session is already set up and announced.
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How to find a AS-SET of an asn?
How can we find the as-set of asn?
For Example I have the asn:32934.
I want the as-set?
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BGP with x2 sessions and x2 L3 VLANs - Please Explain
I am learning about Cisco BGP networking now and came across an interesting situation. In my examples, there was one which suggested that two VLANs were configured on Layer 3 in order to run two BGP ...
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How can I reduce latency to Australia from another country? [closed]
I often do a lot of work from the UK to destination networks in Australia be it voice calls or something more benign like gaming. Both of which work best with the lowest RTT possible.
On average the ...
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Can i implement BGP flowspec
This question is for general information about BGP flowspec, Can i implement BGP flowspec to stop DDoS? RTBH isn't what we want because it blackholing all traffic, we want RTBH at Layer 4 level where ...
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Strange BGP routing issue between two public routers. Not able to see subnets
Having a strange issue can't seem to figure out what's happening. I got 2 routers running BGP. Router A is advertising 23.128.128.0/24 subnet and Router B is advertising 23.128.129.0/24. Routing is ...
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JunOS iBGP session not establishing
I have a test environment set up with two Juniper vSRX instances and a L2 network trunked between them and can reach each other on the IP addresses I'm trying to peer them on.
vSRX 1 has an external ...
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Can we have multiple AS number in the same router?
Is it possible to have multiple AS number in the same router?
Example: Routing-Instance A for AS100 and Routing-Instance B for AS200 ?
Please share me some example or configuration.
