Questions tagged [routing]
For questions about routing, the process of selecting to which network path traffic is sent. Consider using a more specific tag if your question is about a routing protocol like BGP or OSPF.
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Static route is not saved - Why?
I have the following configuration. On R1 I do inter-vlan routing. The problem is when I ping the serial interface of ISP1 with PC MA11 the ping packet is not returned to R1. I wanted to add a static ...
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Trace Route RTO in two or more hop but next hop works [duplicate]
Today when I was doing tracert,
in the 2nd & 3rd and also 4th Hop I get RTO but my next hop seems to be reachable. How come it works?
Please answer asap.
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Multiple GRE tunnels towards single host using anycast IP
I'm trying to build the following network architecture:
Where clients try to connect to a backend server (e.g. SSH) by using a Public Anycast IP adddress (1.2.3.4), that routes the client to the ...
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How can I configure a Cisco router 4300 to allow internal server ip:80 to be accessed on public ip:4500
I have an internal web server on port 80. I need help commands maybe to configure port forwarding to access the server on my private network from a public IP
Current running config
interface ...
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2
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Cisco router on a stick with public ip wan (ISP)gateway
I am trying to create a router on a stick with an outside facing sub-interface with a public IP from an ISP. I have tried to configure NAT and routing but I just cant get to ping the internet. I'm ...
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multi-site vpn with only one site reliably addressable from the web at large
i have a small network like so:
site-31:
wan public ip (dynamic) on isp fibre is reachable from the outside world. an automatically updated dns entry is maintained to keep the ip current whenever ...
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For IPv6, How much processing delay difference between using /64 and /127 for Core network interconnection?
I've question about IPv6 routing processing delay.
Lets assume we've got big Core network with huge traffic and many hops.
All router's p2p interconnection addresses are used /127 network.
In my ...
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Destination NAT on Cisco ISR
I know how to perform regular overload PAT in my lab running
sh ver
Cisco IOS XE Software, Version 16.03.09
Cisco IOS Software [Denali], ISR Software (X86_64_LINUX_IOSD-UNIVERSALK9-M), Version 16.3.9, ...
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Colocation Rack Networking
I'm a sysadmin tasked with finding a managed service provider or networking contractor to build out our new colo space networking. I'm hoping to get some input to make sure I don't sound like an idiot ...
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Routing vs Forwarding [duplicate]
What is the difference between routing and forwarding?When the network is a packet transfer network I dont see the reason for routing since forwarding a packet between nodes requires a routing ...
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IPv6 BGP peering via link-local addresses
I'm planning to run BGP with my upstream provider and advertise our global IPv6 prefixes. I'd like to use only link-local addresses between the ISP's router and my border router to make the border ...
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connect two private network using pfsense
I have two pfenses (say p1 and p2) in two separate networks. Each has a public IP. There is an internal network on each side (say n1 and n2). I want to connect these two networks through these two ...
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Shadowsocks direct connection by default [closed]
Is there any way to make shadowsocks (libev without plugins) work only for specific domains, and routing all other traffic directly through my default provider?
I tried this in my "user-rules.txt&...
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Route LAN traffic through ZeroTier on Edgerouter X [closed]
I have bought an Edgerouter-X to sit behind my ISP provided router in my house LAN. The goal of this router is to expose through it's ethernet interfaces a direct connection through my ZeroTier ...
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Multiple hosts with same ip/subnet seperated by router possible?
Bit of a newb question but just curious if it can be done.
Is it possible to have multiple hosts with the same ip/subnet (eg 10.101.30.10/24) each seperated by a layer 3 switch/router, where one of ...
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Tracing a route, from 127.0.0.1 through my network to 20.43.161.105
Greetings in the name of network engineering!
BACKGROUND:
The IPV4 network consists of the following nodes:
Node 0:127.0.0.1
Node 1:10.1.1.1
Node 2:192.168.0.1
Node 3:192.168.1.1
Node 4:210.x.x.x
Node ...
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how do 2 different network communicate with each other
Suppose we have 2 networks with 3 PCs in each. As I understand, they can easily have the same IP addresses, but routers have different public IP addresses(e.g. here 158.127.10.3 and 158.127.10.4). So ...
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Are there any methods of differentiate between a single computer and a NAT router?
As far as I know, a traffic from a NAT router should appear similar to traffic from one computer with a single IP address. If you do not have any access to a network (let's say you are an ISP), can ...
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2
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How Network layer routing actually works in the physical world
This is my first question here, It might be a vague or off topic, I apologise in advance, but I am happy to improve it
Basically I have a somewhat decent theoretical understanding of the OSI model. ...
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PowerConnect 5500 Series VLAN routing problem
My issue is very similar to this link:
Dell PowerConnect 5524 VLAN routing
I have several VLANs
But most importantly
VLAN 1 is the flat 192.168.69.0/24
VLAN 10 is 192.168.0.0/16
VLAN 110 is 10.1.10.0/...
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Connecting L3 and L2 switches with VLAN settings
I have 1 L3 switch with
Static ip - 192.168.0.252
Two L2 switches
Switch A - 192.168.0.250
Switch B - 192.168.0.251
I have created VLANs in L3 switches with 192.168.1.1 and 192.168.2.2 ips abd set it ...
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How should edge switches have their routing configured (when there is a mgmt vlan in the mix)
I'm having trouble with a new network topology we are trying to implement onto our environment. The issue seems to be with the switches. The problem is not relevant to this question but for ...
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bgp and routing
I need a bit of help understanding what is going on in my topology.
I really want to understand why i can ping 1.1.1.1 from r4 but not from r5 or r6.
Please help and advise me.
Many thanks guys
r1
...
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How does a new switch know how to reach the controller in an SDN?
Let's say we have an existing SDN network composed of several switches and a controller. Now say we connected a new switch to the network. Now how would the new switch know how to reach the controller?...
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4
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Who owns the in-between routers displayed when I execute a traceroute command?
When i traceroute a website, i get the IPs of all the routers in the path between me and the website. Who owns all those routers? Are they organized in a particular kind of building?
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Why is congestion collapse from undelivered packets not possible when there's 1 congested link?
rfc 2914 says this:
The avoidance of congestion collapse from undelivered packets
requires that flows avoid a scenario of a high sending rate, multiple
congested links, and a persistent high packet ...
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3
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IGP between 2 routers with an uncooperative router in the middle
I've got two routers, A and B. A gets some routes over BGP over a VPN connection, and has a leg on 10.0.0.0/24. It also can access the whole 10.0.0.0/16 via its default gateway.
B is on 192.168.0.0/...
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If your ISP already has a gateway, why do you need another gateway with NAT to come before a layer 3 switch?
Please bear in mind that I am learning and have never set up a network with routers and switches myself. Also please bear this is sort of going to be loaded question because there are multiple layers ...
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Can you have multiple paths in BGP through different ASes?
In a course about networks in my university, we learnt about how in BGP routes, each AS chooses a single route to each IP prefix (though you may have multiple iBGP routes).
Meaning that in the ...
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Understanding the difference between EUI-64 and IPv6
I understand that Extended Unique Identifier (EUI-64) allows a host to automatically assign itself a 64-bit interface identifier IID for an IPv6 address.
My question is: What is the purpose of using ...
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Is it possible to assign a default gateway per routing interface on a layer 3 switch
Here is the scenario. Currently there is a flat layer 2 network with a single /24 subnet. The intent is to segment that /24 using a layer 3 switch. On the /24 network there exists clients with ...
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Sharing same IP address inside LAN? [duplicate]
Q: if 2 devices A and B share same ip address in LAN, can device A retrive all messages whose destination is device B?
I think this depends on how the LAN is configured.
If it's wireless then device A ...
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Exclude a certain vlan/subnet from layer3 inter-vlan routing
We have new gen aruba (hpe) switches in our environment.
There is a backbone (5412R zl2) which all edge switches are connected to. The edge switches are also layer 3 (2930F). The backbone delivers ...
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Fortigate and ipv6 routing
I have a Fortigate router and my ISP support ipv6. I'm getting a public ipv6 on the Fortigate and also on the computers on the lan (2a02:a18:9041....)
I have not to much understanding of ipv6, but by ...
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In gnss3, why can't I ping my cisco router from my VM?
I have the following network, I have never configured a Cisco router before so I'm having a little trouble. In router R1 I used the following commands to assign an ip to the router:
configure terminal
...
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IS-IS Interface Metric/Cost Calculation Issue in Juniper MX
I am facing a very strange issue with regard to IS-IS Interface Metric / Cost calculation in Juniper MX. We have configured a reference bandwidth of 1000G on all routers.This by definition means an ae ...
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GNS3 subnetting and routing
I have a project assignment that consists of 3 routers, the ISP, and 2 company routers, the ISP can address a network /24 IPv4.
I delegated a /25 to DNS servers and a /26 to one company and 2*/30 to ...
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Possibility of transferring data over the same-level networks, rather than the higher-level network
This is a silly(maybe interesting) question.
Assume four ASes are connecting to the Tier 1 network(A, B, C and D). B is peering with C and D. A is close to B, but too far from C and D to make peering. ...
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The relationship between AS upstreams, downstreams and peers
I find AS1221 is both the upstream and the peer of AS13445 from ipinfo.io/AS13445. However, as far as I know, there is no upstream or downstream relationship when talking about peering. Is anything ...
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Sonicwall TZ105 Site to Site VPN Created can ping gateways but can't ping network from other site
Need help here
Site B
TZ105
x0 Lan 192.168.162.1
X1 WAN 64.x.x.x
X2 LAN 10.0.3.1
Site A
TZ300
X0 LAN 10.0.1.1
X1 WAN 69.x.x.x
VPN tunnel set up as VPN SITE TO SITE and is Green
From Site A I ...
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How does a PIM router know which neighbour is the upstream router?
I understand that certain PIM messages such as Join/Prune and Graft have a field called 'Upstream Neighbour Address' used to indicate the recipient of the message, which is the upstream router for a ...
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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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In multicast, do shared trees exist solely to reduce router processing of (S,G) forwarding states?
I am asking this question strictly at a conceptual level. I am not asking from a specific protocol's standpoint.
Why do shared trees exist in multicast routing? What was the reasoning behind them?
...
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Make printer in different subnet accessible to other subnet
i am creating a network and i want the printer which is in a different subnet to be accessible by all other subnets. The router network is 192.168.10.0/24 further subdivided into /28 subnets.
The ...
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Why Chassis MAC Address is used when advertising EVPN Type 5 routes
In case of EVPN Type 5 or IP Prefix routes advertisement why chassis MAC address or router MAC address is used in addition to VXLAN VNI?
I guess VXLAN VNI is working on same principle like MPLS VPN ...
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3
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Cannot create subinterface
I'm trying to connect 4 networks with 1 router, i created 2 sub-interfaces in the router, when i tried to create the 3rd sub-interface i got this output "%Cannot create sub-interface", this ...
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Is TCP used for data transfer after building the routing tables (using OSPF protocol)
I am trying to understand how Data (video, image, ...) is sent over the network, and what are the protocols and different processes involved. We know that OSPF (L3 protocol) does not use TCP or UDP, ...
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OSPFv3 Convergence Issue between OPNSense & Cisco Router
I have been digging around the internet and have been trying to get IPv6 up and running on my lab. Here is my current layout:
I have been trying to get OPNSense and the Cisco 1900 router to give each ...
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SPAN/RSPAN monitoring VLAN vs Interface
I am a little lost with regards to the concept of capturing every traffic passing a core switch. If we set our monitor source to be all VLANs in a L3 switch, does that mean that traffic coming from a ...
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What are all the reasons for using a separate /31 subnet for a p2p link?
For example in this LAN, the 13.65 and 13.66 are a separate subnet between slip and bsdi, but what is the reason that they have a separate subnet?
The only reason i can think of is that bsdi cant have ...
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