The eth0 name is short for Ethernet interface number 0 – Ethernet is the dominant networking technology (after winning the 1980s protocol wars) and 0 is from IT’s traditional way of counting (no, there is no good reason to start from 0 instead of 1).

The lo interface is only meant for use within this EC2 machine, not to talk to the outside world.

The lo name is short for loopback, a name left over from the days of soldered wires.

It’s the same for the system administrator – the CLI (Command Line Interface) fills up with data and you learn to see the good stuff and filter out the rest.Īll that information displayed by the ip addr command is organized into two numbered sections, for the two network interfaces, lo and eth0: In the land of film and TV, the sound engineer has to listen to a constant barrage of noise and learn to pick out the details that are important. As with all common collective terms like “server” and “cloud”, “interface” is an easy way to describe the big picture but not so great for details. At this low level, you have to take more care describing your work to others. That’s a dozen lines packed with details, written in a shorthand that makes it hard to read. Use the ip addr command to display lots of information about your EC2 network ~]$ ip addrġ: lo: mtu 16436 qdisc noqueue state UNKNOWN These are collectively referred to as “the interface”. Each network socket has a stack of names and addresses (MAC, IPv4, and IPv6) and a stack of networking software to do the talking.

The name of your EC2 network interface is eth0Įvery physical computer has sockets with cables plugged into them and so does your virtual EC2 machine. Why is it so confusing? And how can you decipher what it means?Ĭonnect to your AWS EC2 instance, find your network interface and its IPv6 address, and let’s do some serious IPv6 breakdown. A few companies have tackled IPv6 but to most it’s just plain confusing. There’s a lot of meaning packed into that strange-looking identifier. When you fire up an EC2 virtual machine, you get an IPv6 address like this. Amazon supply IPv6 addresses with their EC2 cloud computers. Let’s take a long hard look at an IPv6 address. For more info, visit our Terms of Use page.

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We may be compensated by vendors who appear on this page through methods such as affiliate links or sponsored partnerships. Nick Hardiman explains the seemingly arcane engineering of the IPv6 address. Breaking down an IPv6 address: What it all means

What are the rules of ipv6 compression