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.
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Upgrading Cisco 819 to 809, can I connect devices to 2 routed ports and be on same subnet?
The company I work for has multiple remote "IoT" style sites connected back to the datacenter via a Cisco 819 cellular router. We are in the process of upgrading these to the newer Cisco IR809 routers ...
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Assign an IP address based on switch port
Short:
I want DHCP server to assign a preconfigured IP address based on a port (on a switch, ideally) a device is connected to.
Long:
My situation:
I am building an automated indoor farm (for ...
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What do these three options in a Cisco Router NAT configuration mean?
In a standard Static PAT configuration, where one IP:Port combination is always mapped to another IP:Port combination, there are three possible combinations of inside/outside/source/destination that ...
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How are MAC/IP addresses used in routing
I have to teach my sixth form about MAC Addresses and IP Addresses in a few weeks time and there are some areas I am unclear on which I am hoping some of you will be able to clarify for me. I have ...
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How does a router know to which PC in a network to send a response from a server?
When my PC sends a request to a server, the transmitted IP address is the one of my private network. When the server responds to the request, how does the router know to which PC in the network to ...
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how do i connect two networks with two routers in packet tracer?
I am am new to networking and I have recently started using packet tracer. I`m trying to get familiar with sub-netting and I've made a simple network that is going terribly wrong. I have 4 departments:...
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Difference between control plane, data plane and management plane?
I think I understand these concepts, but I'm a little rusty. Can someone give a concise, easy-to-understand explanation of these concepts? The planes are logical concepts, aren't they? Is this a Cisco ...
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Bad Mask for IP Address Error
I'm not too clear on subnetting rules and experienced an error when I tried to assign 148.26.1.176/28 to an interface on my Cisco router. Can someone please explain why it was not allowing me to ...
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DHCP relay problem on interfaces secondary network
A secondary network was configured on an interface of a Cisco 2621 router and the ip helper-address commands put in place but no clients of that secondary network could pull DHCP addresses. We swapped ...
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What is a "Layer 3 Switch"?
What is a "Layer 3 Switch"? I essentially understand the OSI model, well maybe I don't and maybe that is why I don't understand. Its just that I don't see how/when/if a "managed switch" becomes a "...
- 111
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Static routes: numerical next-hop vs interface
I'm reviewing old Cisco modules, and in CCNA 2, Module 2.5.1.2, it states,
Under certain conditions, the network administrator will not want to configure the static route with an exit interface but ...
user3046
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Why are routers not answering ARP Broadcasts?
Host A wants to send something to Host B who is in a different network. Between them is Router 1. Host A sends an ARP broadcast but Router 1 is not answering it. Why is that so?
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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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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 ...
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Collision domain question
I'm studying for my CCENT exam, and not quite sure why the book (official Cisco) says that there are 5 collision domains in this example. Isn't it supposed to be 4? The hub on the left, the hub in the ...
