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Questions tagged [networking]

Networking refers to the technologies and techniques that enable the interconnection of devices and applications allowing them to communicate electronically.

Networking refers to the technologies and techniques that enable the interconnection of devices and applications allowing them to communicate electronically.

Originally referring to local-area networks (LANs) designed to allow communication between computers in the same office or university, networking now covers a broad swathe of topics. To name but a handful:

  • small-office/home-office
  • campus/metro area networks (MANs)
  • datacenters
  • wide-area networks (WANs)
  • optical networks
  • telephone networks
  • Voice over IP
  • wireless LAN
  • cellular telephony
15498 questions
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How does IPv4 Subnetting Work?

This is a Canonical Question about IPv4 Subnets. Related: How does IPv6 subnetting work and how does it differ from IPv4 subnetting? How does Subnetting Work, and How do you do it by hand or in your head? Can someone explain both conceptually…
Kyle Brandt
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I've inherited a rat's nest of cabling. What now?

You know, you see pictures like below and sort of chuckle until you actually have to deal with it. I have just inherited something that looks like the picture below. The culture of the organization does not tolerate down time very well, yet I have…
Chad Harrison
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What is the difference between Unix sockets and TCP/IP sockets?

It's from this answer: https://stackoverflow.com/questions/2482411/is-this-pdo-bug-fixed-now/2482424#2482424 When the host is "localhost", MySQL Unix clients use a Unix socket, AKA Unix Domain Socket, rather than a TCP/IP socket for the connection,…
apache
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Setting the hostname: FQDN or short name?

I've noticed that the "preferred" method of setting the system hostname is fundamentally different between Red Hat/CentOS and Debian/Ubuntu systems. CentOS documentation and the RHEL deployment guide say the hostname should be the…
Cakemox
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VirtualBox: How to set up networking so both host and guest can access internet and talk to each other

I was wondering if someone could give me a simple guide on how to set up virtual networking in VirtualBox (4.0.2) so that the following scenarios work: Both Host and Guest can access the Internet Host can ping Guest and vice versa Host can access,…
Svish
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Should I quit using Ifconfig?

With the servers that mount Infiniband cards, when I use the ifconfig command, I get this warning: Ifconfig uses the ioctl access method to get the full address information, which limits hardware addresses to 8 bytes. Because Infiniband address has…
Zhen
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Resolve host name from IP address

I'm looking for a command line tool which gets an IP address and returns the host name, for Windows.
DouglasJose
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Why couldn't MAC addresses be used instead of IPv4|6 for networking?

I am reading up on TCP/IP and other related protocols and technologies. MAC addresses are described as being (reasonably :) unique, and as having a large possibility space (several hundred trillions), while also being assigned to all network…
Félix Saparelli
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What causes the 'Connection Refused' message?

This is a Canonical Question about Connection Refused We see a lot of questions to the effect When I try to connect to a system I get a message Connection refused Why is this ?
user9517
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How do VLANs work?

What are VLANs? What problems do they solve? I'm helping a friend learn basic networking, as he's just become the sole sysadmin at a small company. I've been pointing him at various questions/answers on Serverfault relating to various networking…
Murali Suriar
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Why do consoles sometimes hang forever when SSH connection breaks?

I've seen this with so many consoles (on Linux, Mac, ...), and with lots of different machines in many different networks. I can never pinpoint the exact reason, why this happens: All you have to do is log in to a machine via SSH. If the connection…
Chris Lercher
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In Windows, using the command line, how do you check if a remote port is open?

What is a simple way in Windows to test if traffic gets through to a specific port on a remote machine?
Matt
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How does IPv6 subnetting work and how does it differ from IPv4 subnetting?

This is a Canonical Question about IPv6 Subnetting. Related: How does IPv4 Subnetting Work? I know a lot about IPv4 Subnetting, and as I prepare to (deploy|work on) an IPv6 network I need to know how much of this knowledge is transferable and…
Michael Hampton
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How to forcibly close a socket in TIME_WAIT?

I run a particular program on linux which sometimes crashes. If you open it quickly after that, it listens on socket 49201 instead of 49200 as it did the first time. netstat reveals that 49200 is in a TIME_WAIT state. Is there a program you can…
Rehan
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Switching to IPv6 implies dropping NAT. Is that a good thing?

This is a Canonical Question about IPv6 and NAT Related: How does IPv6 subnetting work and how does it differ from IPv4 subnetting? How can I 'dip my toes' into dynamic IPv6 network addressing? IPv6 without nat but what about an isp change? Our…
Ernie
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