Questions tagged [router]

For questions about network routers, devices that forward data packets between computer networks, commonly at the network layer (layer 3) of the OSI model.

1
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1answer
70 views

OSPF inter-area traffic - not so direct after all

a) Can I confirm inter-area traffic will be routed towards Area 0 / Area 0 will be the transit network for all inter-area traffic? b) Consider the diagram below q1) Does R1 receive Type 3 LSA for ...
3
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2answers
334 views

What's the difference between Ethernet link and Serial link?

Sometimes we see router connected use Ethernet link, sometimes use Serial link, what's the difference between them? and in what scenario we use them?
2
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2answers
60 views

If the Router's Gig0/0/0 to its Gig0/0/1, whether only cost one TTL value?

I have questions about the TTL value. whether the Router3 Gig0/0/0 to Gig0/0/1, there will cost one TTL? if the Router2 Gig0/0/0 to Router3's Gig0/0/0, will there cost one TTL? or do not cost? if ...
6
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3answers
1k views

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 ...
5
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1answer
134 views

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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0answers
54 views

Whether the OSPF ABR Router's loopback network should announce to Backbone Area? [closed]

The OSPF ABR Router whether its loopback network should announce to Backbone Area? the upper snapshot shows the C,D,E are ABR Routers, if everyone has its own loopback networks, I want to know ...
2
votes
1answer
203 views

What's the definition of Router Link and Net Link?

When I show the ospf database: Router2#show ip ospf database OSPF Router with ID (2.2.2.2) (Process ID 1) Router Link States (Area 0) Link ID ADV Router ...
1
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1answer
82 views

What's the relationship of a Router with its loopback interface in logic?

I have a Router1 with a loopback 0 connected to the Router2: the interface brief is bellow: Router1>show ip interface brief Interface IP-Address OK? Method Status ...
2
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1answer
214 views

Configuring multiple subnets with switch connected to single router interface

I have a design like this But I'm receiving a lot of mismatch errors and it doesn't work at all. I tried to ping 10.0.0.1 to no avail. I'm trying to configure the vlans on the switch 1 this way (...
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3answers
196 views

Why the OSPF router do not have neighbor?

I have two Routers in the Cisco Packet Tracer: Router2-1, Router2-2, Router2-3 all have their own loopback 0 with IP address 1.1.1.1, 2.2.2.2, 3.3.3.3. I only launched the OSPF progress in the ...
4
votes
1answer
193 views

Whether every router in a AS must have its RouterID?

Whether every router in a AS must have its RouterID? I know if a AS want to use BGP, the routers in the AS must have its own RouterID. whether a AS want to use router protocol, the routers must ...
4
votes
1answer
299 views

Whether the Vlan10 and Vlan20 in the Center Router are two virtual router interfaces?

I have a ISP 4321 Router in my Cisco Packet Tracer. and I added a NIM-ES2-4 module in the Router, that provides four switching ports. and now, I configured two VLANs to the two switch port of them. ...
1
vote
1answer
332 views

Is there any router port module of the Cisco Packet Tracer Router?

In the Cisco Packet Tracer: there are a list Routers, you can see such as 4321, 1941 and so on. but I tried everyone, there is no one have a module with multi router ports. there are switching ...
2
votes
2answers
555 views

The ISR 4321 only have two router ports

I have a ISR 4321 Router in my Cisco Packet Tracer, and I added a NIM-ES2-4 module, but the The NIM-ES2-4 provides four switching ports. which are Gig0/1/0 - Gig0/1/3. because I want to use the four ...
6
votes
1answer
67 views

How to set IPv6 RA values for RDNSS and DNSSL on HPE/Aruba 5400R

I am detail-planning the roll out of IPv6 in our company. Right now I am stuck with IPv6 RA on our HPE/Aruba Access Switches. I cannot find any documentation how to set the Recursive DNS Server (RDNSS)...
1
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1answer
90 views

Why RIP announce network does not need the mask?

The below is the RIP protocol's declaring the routing command: Router(config)#router rip Router(config-router)#version 2 Router(config-router)#network 1.1.1.1 Router(config-router)#network 192.168....
1
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1answer
61 views

Does the Router running multi routing protocol progresses received the routes will store into the Forwarding table?

I have a question about the Router running multi routing protocol progresses. if the bellow snapshot R1 have EIGRP and OSPF progresses, if the EIGRP progress received the routes from R3, will it store ...
4
votes
1answer
66 views

Does one logical router have only one route table?

If a router running several IGP, such as two EIGRP processes, one OSPF: Will all the IGPs processes' acquired routes be stored in the router's one and only route table or more? I mean, two ...
1
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2answers
447 views

How to assign all interfaces in one router to OSPF backbone area?

Is there any command to assign all interfaces in router (CISCO 2691) to OSPF backbone area? I was using this command for each interface. network address wildcard-mask area area-id Where wildcard ...
1
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2answers
153 views

Why Do we consider the serial connection between routers a subnet?

The image attached was included in a question where I was required to design the network f0r the classful network address 172.16.0.0, and it says that each circle represents a subnetwork. My question ...
1
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1answer
288 views

Quagga - Configure 3 routers using OSPF

Hi I'm trying to use quagga to connect 3 routers but the middle one doen't complete the path that a trace route command would do even though it knows where the target address is. It seems that ...
6
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0answers
256 views

How to control unwanted UDP traffic (Broadcast & Multicast) on Cisco Router 2911?

Please suggest, we are getting UDP traffic either broadcast or multicast in router 2911 which cause 95%+ utilisation of the router. And we got error in link and business impact due to this. Company ...
3
votes
2answers
124 views

After I set the “router rip” networks, how can I check it?

In my CGR1240 I have set network 192.168.1.0 to my router rip, but how can I check it? If I add more networks in rip, how can I list all the networks I have added? I can not show the router rip in ...
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2answers
902 views

How can the Cisco Packet Tracer show the port's name?

How can the Cisco Packet Tracer show the port's name? the GNS3 can show its interface name.
5
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1answer
577 views

What's the role of Router/Switch name number?

I have a CGR1240 Router in Cisco Packet Tracer: I have a question about the name of port. I have no idea about the name number of a router/switch port. why there is 2/* in CGR Router? such as ...
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0answers
35 views

How to check my Cisco Switch and router [closed]

I have bought a Cisco refurbished router and Switch how to check it's all OK to use ? any commands ?
2
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1answer
517 views

Can VPN on router connected to the modem bypass a double NAT created by two routers unbridged and connected to each other?

I can't seem to get my head around this scenario. If I am right, a VPN configured on the client-side/workstation would definitely bypass double NAT but on this scenario: Modem <-bridged-> Router ...
1
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1answer
33 views

How to check a Switch GE port's link-type?

How to check a Quidway Switch GE port's link-type? I have a S5700 switch, and I want to check its GE0/0/1 port's link-type whether is access. I have tried use bellow command: [Huawei]display ...
2
votes
0answers
52 views

error when try to connect my router/switch to putty/teraterm [closed]

I get the following error when I try to connect to my router or switch. i checked it with both putty and tera term but the error remains the same
5
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1answer
475 views

How does router advertisement in IPv6 avoid IP conflict?

If a router advertisement sends the range of subnet, and the client can choose an IP from it, how is there no conflict with another client that has chosen the same address?
0
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1answer
38 views

If I disable the 5GHz radio on my router will it improve my 2.4GHz performance or range? [closed]

I am having an ASUS RT-AC53 dual-band router having 3 antennas. Currently, it is emitting both the 2.4GHz and 5GHz wifi radios. I am just curious if I disable the 5GHz radio will it anyway improve the ...
4
votes
1answer
144 views

What is the exact meaning of routes in Juniper tagged with @ and #

The routing table explains the meaning of these symbols as: @ = Routing Use Only, # = Forwarding Use Only + = Active Route, - = Last Active, * = Both However, I am looking for more detailed meaning ...
1
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1answer
45 views

What's the meaning of “3D Universal Edge Routers”?

What's the meaning of "3D Universal Edge Routers"? I often see this term on Internet, but I do not understand what it stands for. Such as "MX240 3D Universal Edge Router", "MX480 3D Universal Edge ...
3
votes
1answer
77 views

Managed switch uplink without “no switchport”

Say you have a L3 switch routing between VLANs 10, 20, and 30, and you need to uplink the switch to a router for the VLANs to get to the rest of the network. The VLANs don't traverse between sites. I ...
2
votes
1answer
364 views

DHCP relay on Juniper MX

Hi I got a problem with bootp relay on a juniper router(s). I got helpers bootp interface configured with: irb.10 broadcast server 10.20.1.10 server 10.20.1.11 theres several irb ...
1
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1answer
43 views

Is the Backbone Area connected AS Area are through one router?

I am studying Networking, and I find the Area 0.0.0.1, Area 0.0.0.2 connect to the Backbone Area is through one path, is it means only through one router(or say not more)? we often hear that the ...
4
votes
1answer
420 views

What does 'parent interface' mean with respect to VLANs?

I'm trying to learn about VLANs by configuring a router with PFsense installed. Reading the documentation I came across the following sentence: The following example shows how to configure two ...
1
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2answers
62 views

Old 2611 and desired features

I just recently got my CCNA and bought some routers from the teacher that he had laying around to do some home labbing. While two of them are good and more modern, the third one is an old 2611 from ...
3
votes
1answer
697 views

Data link layer acknowledgement

I'm confused with some concepts please help me out, Data link layer manage flow control hop to hop. Flow control requires acknowledgement receiving but If we observe data link layer header, it does ...
1
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1answer
53 views

Pros and Cons of two different ISP connection Model

I have seen two different models to connect My Server to cloud. Model 1: DNS ------| |---ISP_Router---Cloud----DSL Modem---Office_Router---Switch---My_Own_Web_Server Google ------| ...
3
votes
1answer
50 views

what is the point of making directories in a cisco cli

what is the point of making directories in a Cisco router. I noticed its was kinda like Linux mkdir and all that stuff, but what is the purpose?
1
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1answer
70 views

What hardware do I need to assign IPs based on port?

Similar (but different) question: Assign an IP address based on switch port I regularly need to test our hardware products. Usually that consists of having ~50 devices sitting on a bench for some ...
3
votes
2answers
83 views

Why can't I get a WiFi password by sending out the same SSID?

If I have two WiFi routers in different locations but with the same SSIDs and I connect a device to one of them, when I bring this device near the location of the other router, it will automatically ...
2
votes
1answer
246 views

Assign DHCP IP address on Cisco router interface

Hi, dhcp router is configured with following DHCP settings: ip dhcp pool B network 192.168.1.0 255.255.255.0 default-router 192.168.1.1 ip dhcp pool C network 192.168.2.0 255.255.255.0 default-...
0
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1answer
45 views

4G connection PLC [closed]

I'm trying to control online a Siemens' PLC. 1200 series. I'm using a router 4G (TP-LINK) with a SIM card. I created a DynDNS in the router with NOIP.com but I can't communicate with it. The ports ...
1
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1answer
2k views

how to deny ping from one direction but not the other using Access-list

Hello everyone. What I'm trying to do is to deny ping access from the 12.12.12.0 network to reach the 10.10.10.0 network but not deny ping access to go from 10.10.10.0 network and reach the 12.12.12....
5
votes
3answers
4k views

Do routers change MAC address of packets when forwarding

Lets say host A wants to send a packet to host B through R1(interface 1 then 2) and R2 (interface 3), so my questions is: When the packet is forwarded inside R1 (from interface 1 to interface 2), ...
1
vote
1answer
50 views

Does segment routing protocol steer packets based on best (longest) prefix matching?

In segment routing protocol, we know that the routing process is source steered. I'm struck to know if any best (longest) prefix matching happens to route the data packets? If so any clue about the ...
6
votes
3answers
1k views

How not to route on a Cisco router

So we have a router, with a switch card interface, 8 ports Say I have 4 VLANs (A,B,C,D) on it, with 2 switch ports in each. Each VLAN (i.e. all ports) can communicate with each other, because ...
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1answer
209 views

Can't save configration in router(gns3 )

I have installed gns3 v2.1.9 with gns3 vm(oracle v5.2.18) in my Ubuntu 64bit v18.04. I have installed 2 routers 3725 and 3745 in gns3 vm. But if i try to save my config with copy running-...