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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.

4
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0answers
89 views

Where is the traffic going?

Here is a routing puzzle: I'm working on a poorly documented network, and I'm trying to document things as I discover them. R1 is a core L3 switch. R2 is a router. The FW is a, well, firewall. On ...
2
votes
2answers
329 views

Default gateway of host connected to two routers via switch

I wanted to make this network fully connected, so I need to assign IP addresses to all interfaces of routers and to all hosts. However, I should assign a default gateway address to every host, but, ...
2
votes
1answer
169 views

Successful Intervlan Routing on a Layer 3 Switch, Unsuccessful IP Routing

Hello and thank you in advance for your help! I'm using Packet Tracer for testing purposes and I' m trying to implement a simple intervlan routing in a Layer 3 Switch (3560-24PS) and an IP Routing. ...
6
votes
1answer
1k views

Dealing with IP Spoofing

Border routers, which are routers that span two or more sub networks, can be configured to block packets from outside their administrative domain that have source addresses from inside that domain....
2
votes
1answer
46 views

Can mobile devices take a global IPv6 address by means of only routing?

I'm probably asking this the wrong way, but here it is; I have a /48 block with static addresses for every device on the network. Everything is routed, no NAT, no tricks. My question is: on a mobile ...
1
vote
0answers
79 views

Cisco ISR Zone Based Firewall dual stack not matching returning traffic for ipv6

I have a bit of a problem with my Cisco 1921 ISR config. I have ipv4 (obviously) and also native ipv6 connectivity in my home lab. I am trying to set up the zone based firewall. With ipv4 traffic, the ...
2
votes
3answers
470 views

Does a router send frames or packets?

Perhaps it's a novice question, but does a router send/receive frames? When I read about this subject, it seems that routers decapsulate the frame on arrival, and encapsulate the packet in a frame in ...
3
votes
2answers
61 views

Why isn't web traffic blocked by router?

(A naive/stupid question which I couldn't find answer to on the web.) Why is the internet traffic reaching me even if I haven't set up port forwarding. (For example, I can view websites). What I ...
0
votes
2answers
60 views

How to connect several standardized networks to a common network?

Imagine, if you will, a series of custom built modules (building size). Each module is setup with standardized control/automation equipment (PLC's, VFDs, HMIs etc.) which communicate to each other, ...
0
votes
0answers
14 views

How to connect private networks? [duplicate]

I need to connect two private networks. I have the same IPv4 addresses and need to establish connection between them. • How can I connect them? (NAT?) • What type of routing to use? (I know static ...
2
votes
2answers
501 views

Cisco 899G-LTE Cellular 0 interface in spoofing mode

I have a problem. After I've reseted my router configuration it doesn't get IP from LTE SIM card. Seems like my celullar0 interface is in spoofing mode. > Router#show interfaces cellular 0 ...
1
vote
2answers
52 views

Make devices visible under Access Point

In our network, all wired PCs have a direct access to internet (83.XX.XX.XX) and a secondary IP address on the same NIC in order to access a subnetwork (192.168.10.XX) with wired peripherals (scanners,...
5
votes
2answers
134 views

I want to understand Cisco's packet forwarding mechanisms

I want to understand how Cisco's CEF and Fast Forward cache packet switching is better than process switching, and I think I might be having trouble understanding Cisco's language. When they say ...
0
votes
1answer
105 views

Private IP vs MAC

What I know is that when we connect to another IP, our Public IP gets shared to the outside world, and when they address us they use our Public IP (gateway), and then the gateway directs the ...
3
votes
1answer
72 views

Cisco Router IOS update

I am facing problem in update the IOS of Cisco 7304 router. I am upgrading from 12.4(24)T2, to 15.2(4)S7 this. but I was boot from this version 15.2(4)S7 it booted proper from flash. But when I put ...
2
votes
1answer
53 views

Is it worth the effort to split up in layer 3 with point to point links? [closed]

I have this technical question. With my family we have a little business. I got to provide internet access to three places, separated a few hundred meters each other. I need to allow to watch the ...
11
votes
8answers
5k views

Why are IP addresses given to each interface and not device? What would the implications of that be?

Why do we need to give IP addresses to each interface? Wouldn't giving one to each device be enough?
0
votes
1answer
40 views

Routing a packet for directly connected network

We have a 3rd party Router code for our networking product. I am a novice networking developer and do not have much idea on routing. However we are facing a scenario for which we seek solution. The ...
5
votes
1answer
130 views

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, ...
0
votes
1answer
34 views

Connectivity from DHCP-based machines to servers with static IP addresses on the same gateway

I have Comcast service with 5 static IP addresses, using a Cisco DPC3939B as the cable modem. In addition to the 5 machines with static IP addresses, there are additional devices that get their IP ...
4
votes
1answer
61 views

Extending a subnet across a WAN link vs routing

probably a noob question but any help is appreciated. Question: What are the disadvantages of spanning L2 subnets across a WAN as opposed to a routed connection? Background: I've got a client who's ...
5
votes
2answers
929 views

How does a router know the MTU of a network?

I've done several exercises where you're given the MTU of a net or subnet, but I wonder how routers know the MTU of the nets they're connected. I've learnt that in OSPF protocol this information is ...
0
votes
1answer
62 views

How are websites accessed without port numbers?

I am confused on how requests to websites are received. If I type in 172.217.5.110 to my browser, google.com sends me its home page. I didn't have to specify the port number. How does that work? I ...
2
votes
1answer
109 views

Cisco ASA Dial in VPN access Devices on Site-to-Site VPN

Questions 1) What do I need to run to get this to allow the on-site to talk to the dial-in network clients E.G ping from 10.101.1.7 to 10.101.2.1? 2) What do I need to run to get the dial-in network ...
3
votes
2answers
552 views

How many pps (64Byte each) i can receive in 1Gbps throughput modem / firewall

I need help with this: If i have 1Gb/s throughput. I can receive how many pps in 64Byte each packet / s? Let's say I can send (Packet / Second - 64Byte) 450,000, meaning I would not only have 230.4 ...
1
vote
1answer
173 views

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 ...
0
votes
1answer
31 views

If all corporate (large scale) networks require routers

Wondering if all large-scale networks require routers or if there are other devices or things that are used in practice in some corporations instead of routers that solve the same or similar problems ...
1
vote
1answer
29 views

Multiaccess link show two Designated Routers in area 0

I have 4 cumulus routers setup with a single ethernet connection from r3 -> r1 -> r2 - r4. From r1, show ip ospf neighbor displays the following: **Neighbor ID Pri State Dead Time ...
1
vote
1answer
79 views

Accessing internal website from subnet

I have the following network: - Edge Lite 3 router with public IP on WAN (eth0) and 2 LANs: 1) eth1 192.168.1.11/24 2) eth2 192.168.2.11/24 eth1 is DHCP, I have several work laptops inside. eth2 ...
3
votes
1answer
659 views

the meaning of static routes and next hop

i configured a network topology on cisco packet tracer to learn about the static routing, as shown in figure below i spent a lot of time to ensure the connectivity between server0 and server2(cause i'...
2
votes
1answer
88 views

How to make PCs in the same LAN but on different networks communicate

Is it possible to ping PCs in the same LAN but on different networks? I've done RIP version 2 on all the routers. They all can ping each other. However, the PCs cannot. For example, when I try to ping ...
1
vote
1answer
32 views

IP Routing question

We are in the process of replacing our firewall and are keeping the VPN client traffic on the older device. The public IP range is being split between the two devices from our border router. All the ...
2
votes
3answers
257 views

connect a cisco router to the internet through a cable modem

The router gets an External IP address via DHCP from the Cable modem Clients inside the network get an IP address from Router's DHCP server I can ping that the external IP address from a client inside ...
3
votes
1answer
187 views

What is the difference between “set community” and “add community” in juniper?

I am trying to understand setting up policies on a juniper router. What is the difference between "add" and "set" community? set policy-options policy-statement MY_POLICY term MY_TERM then community ?...
2
votes
3answers
77 views

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 ...
4
votes
1answer
330 views

Will the data transfer with the destination on the same LAN network be routed through the internet when the WAN IP is used?

I'm planning to set up a Nextcloud locally. I will be using my own domain with a DNS record to connect to my WAN IP and port forward the needed ports to the local machine running Nextcloud. Now of ...
0
votes
1answer
37 views

IGP vs LDP forwarding

By default when MPLS and LDP is configured in a cisco IOS/IOSXR and some IGP. If I forward a packet toward internal IP. Router will use MPLS to get destination. When show the routing table I only can ...
0
votes
1answer
59 views

A new version of RIPv2 using different keys for each router

There's a problem in a textbook that is really stumping me. How would you enhance the RIPv2 protocol to provide a (more) secure and scalable schema for distributing the updates? Describe the ...
2
votes
1answer
75 views

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 ...
3
votes
1answer
72 views

WISP Network Edge Device - Router vs Switch

I am faced with an issue right now working for a small rural WISP. We have roughly 250 wireless customers throughout our area using Ubiquiti radios. Our main fiber drop comes in from a larger ISP on ...
4
votes
1answer
366 views

Juniper SRX 240 - Routing subsystem not running on secondary node

Does anyone know why rpd would not run on secondary node? Thanks
0
votes
1answer
210 views

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 ...
1
vote
1answer
65 views

Networking Questions (Routing and Switching)

I inherited a haphazard network that I'm in the process of cleaning up and modernizing. Here is a synopsis of the current issue: We have a MySQL DB hosted on a Windows 7 PC (solely used to host the ...
1
vote
0answers
117 views

OSPF over IPIP tunnel doesn't work for CSR 1000v in AWS

I literally have the following topology shown in the figure below. I have 4 VPCs, each VPC has 3 subnets (1 for the VM instance and the other 2 for interfaces). Each VPC hosts a Cisco CSR 1000v in ...
0
votes
1answer
122 views

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 ...
1
vote
1answer
115 views

Users on one VLAN cannot access multicast resources [closed]

Feel like I'm getting closer to fixing my issue... This is the simplified version of the multicast... -No RPF Failure -pim sparse mode on all interfaces -multicast routing enabled I forced a group ...
2
votes
2answers
477 views

IPv6 can't ping host when static route configured with exit interface

I have the following topology (using IPv6) interfaces: I have the following static routes configured on it: R1#sh ipv6 route static IPv6 Routing Table - default - 9 entries Codes: C - Connected, L -...
0
votes
1answer
154 views

How to create interfaces for CSR 1000v for GRE tunnels?

Well, my idea is to connect to 4 CSR 1000v routers in different VPC (without VPC peering). I've basically finished with everything with the pre-configuration creating VPCs, subnets IGW, modifying ...
1
vote
2answers
38 views

My ip address changes daily. How can I setup port filtering so that I can access my VM via RDP without adding the new ip everyday?

So I have a VM in Azure. I would like to ensure that only I can access it. I setup port filtering so that only my IP is accepted, and only from port 3389. The next day my IP changed, but only the ...
3
votes
1answer
473 views

I can't set a gateway of last resort

I can't seem to get to set a gateway of last resort on a router. I want it to forward anything whom's ip address is not in the routing table to router HQ through interface s0/0/0 by doing the ...