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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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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29
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What are the benefits and cons of IGMP snooping?
Our new router is asking if we want IGMP snooping enabled. Not being familiar with this, I looked to the internet and got the following wiki description:
IGMP snooping is the process of listening ...
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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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What stops someone from configuring their network with IP addresses they do not own?
Here's the scenario. I was picturing a university that bought a range of IP addresses. I think their network would still be connected to an ISP (right?), but they'd have freedom to configure stuff the ...
- 553
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Difference between router and gateway
What is the exact difference between router and gateway? In Network configuration we set the default gateway IP address, but in reality we call the device configured with that IP address as router?
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Building new network and need 200+ wireless devices
I'm planning the network for my company's new office space. I'm not an expert so I'd like to present my plan and ask y'all nice folk to tell me if and where I'm making mistakes.
Assumptions:
Office ...
- 693
19
votes
4
answers
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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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Cause of high CPU load on Juniper peering router's routing engine
Recently the routing engine CPU utilization on two of our Juniper peering routers increased from ~10-20% average load to 80+%. I'm trying to figure out what's causing this (and how to get this high ...
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18
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7
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Cisco command to show which interfaces an ACL is applied to
For Cisco routers and switches, is there a show command, or something similar, that will display what physical and logical interfaces an ACL is implemented on and what direction it is applied in?
I ...
- 3,129
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Backing up Cisco router configuration - including ssh keys
We have some Cisco 2821, 2921 and 1921 routers in our shop. I can back up and restore the configurations by copying out or in the startup-config file, but what about the keys for ssh? I don't want ...
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Why would a switch be connected to a router using three ethernet cables?
In our rented office, we have a router (BT smart hub) connected to a large switch (model unknown). The two are connected using three ethernet cables, thus:
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| 1 2 3 4 ...
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Automate configuration backup (every minute) in Cisco IOS
I'd like to make my Cisco router automatically do a copy run TFTP (and populate the fields automatically) every 1 minute. I'd also like it to be run in the background. Anyone know if this is possible/...
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Is it possible to specify a route for a packet to take?
So, AFAIK, packets "hop" between routers. Packets are forwarded via a router's default path until it gets to destination IP. So is it possible to specify a specific set of routers this packet "hops" ...
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Output Drops on Serial interface: Better queueing or Output queue size?
On Internet edge routers speaking eBGP to multiple carriers and iBGP to one another, all interfaces on the LAN and WAN side are GE except for one Serial full-DS3 (~45Mbps) on each router. Although I ...
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BGP multipath with different ASNs feasible for production networks?
on Cisco (this command is hidden for some reason)
#bgp bestpath as-path multipath-relax
The default BGP behavior only installs only routes with exact the same AS_PATH into RIB. With multipath-relax, ...
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