193 votes

Why is my ethernet interface called enp0s10 instead of eth0?

Answer on "What does enp0s10 means?" question: enp0s10: | | | v | | en| | --> ethernet v | p0| --> bus number (0) v s10 --> slot number (10) Source: udev-builtin-...
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136 votes
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How can I create a virtual ethernet interface on a machine without a physical adapter?

Setting up a dummy interface If you want to create network interfaces, but lack a physical NIC to back it, you can use the dummy link type. You can read more about them here: iproute2 Wikipedia page. ...
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107 votes
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Why is my ethernet interface called enp0s10 instead of eth0?

That's a change in how now udevd assigns names to ethernet devices. Now your devices use the "Predictable Interface Names", which are based on (and quoting the sources): Names incorporating ...
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40 votes

Naming convention standard for Ethernet and Wi-Fi interfaces on Linux machines

Network interfaces can be named anything, so no matter what you do, you'll run into situations where (1) there is a "physical" network interface with a name that didn't match your pattern, or (2) ...
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37 votes

Why is my ethernet interface called enp0s10 instead of eth0?

As mentioned above, enp0s10 refers to ethernet (en), prefix 0 (p0), slot 10 (s10). The bus number, device number, and function number are pulled from the Bus Device Function (BDF) notation for PCI ...
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  • 472
36 votes

How can I create a virtual ethernet interface on a machine without a physical adapter?

You can create virtual interfaces using the iproute2 toolkit. ip link add veth0 type veth peer name veth1 This will create 2 interfaces, veth0 and veth1. Think of them as 2 ends of a pipe. Any ...
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29 votes

Can I connect a Ubuntu Linux laptop to a Windows 10 laptop via ethernet cable

Yes, as I have done this before, but with Ubuntu-based distros connected to Windows Vista. However this should still work with Windows 10. This is called a direct ethernet connection. There are a few ...
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  • 3,449
28 votes

Naming convention standard for Ethernet and Wi-Fi interfaces on Linux machines

For systemd predictable interface names, the prefixes can be seen in udev-builtin-net_id.c : * Two character prefixes based on the type of interface: * en — Ethernet * ib — InfiniBand * sl — ...
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27 votes
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ip link and ip addr output meaning

Those are interface's flags. They are documented in the netdevice(7) man-page. Below is the relevant part (reordered alphabetically): IFF_ALLMULTI Receive all multicast packets. IFF_AUTOMEDIA ...
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17 votes

How to check programmatically if the Ethernet cable is plugged in?

The 2 methods I've seen used predominately are to use ethtool or to manually parse the contents of /sys. ethtool For example if your interface is eth0 you can query it using ethtool and then parse ...
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15 votes
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Identical MAC address on two different VM, yet I have internet connectivity

This is one of those things that surprises people because it goes against what they've been taught. 2 machines with the same hardware mac address on the same broadcast domain can talk to each other ...
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15 votes

Determine ethernet speed in RHEL 6

Do NOT use mii-tool. It was last updated years ago and does not support anything over fast ethernet. There are few ways you can determine ethernet speed. The most recommended one is cat /sys/class/...
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15 votes
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meaning of "brd" in output of IP commands

brd is short for broadcast. 147.202.85.255 is the broadcast address for whatever interface that line belongs to.
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15 votes
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Bridged interfaces and VLAN tags

Yes: you can set the bridge to be VLAN aware. The bridge will then handle VLAN IDs attached to frames crossing it, including tagging and untagging them according to configuration, and will send a ...
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14 votes
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Linux disables ethernet auto-negotiation on plugging-in the cable?

After hours of searching I found the solution in the most obvious place: NetworkManager seems to somehow have disabled autonegotiation right in the settings for my ethernet port: The weird part is ...
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14 votes

How to get maximum supported MTU size for interface?

Amazingly, I found that ip reports this information if asked. ip -d link list 21: enxa44cc8aa52bd: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc fq_codel state DOWN mode DEFAULT group ...
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12 votes

Device vs network interface IP addresses

Each network interface will have it's own IP address if IP traffic is to flow through it. Take for example, your router/modem device that most homes and/or small offices have. There will a ...
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12 votes
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How do I configure a network interface bridge from WiFi to Ethernet with Debian?

For configuring a bridge from ethernet to wifi, it is as simple as doing in your /etc/network/interfaces: auto eth0 allow-hotplug eth0 iface eth0 inet manual auto wlan0 allow-hotplug wlan0 iface ...
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10 votes

2 IPs on 1 ethernet adapter

There is a Linux-feature which makes your machine reply for every IP address assigned, on every interface, when they share the same IP subnet, regardless of the particular IP-interface assignments. ...
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10 votes
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How can I find active network interface from userland?

Something like this? ip addr | awk '/state UP/ {print $2}' enp0s3: This command was issued as a "regular" (non-root) user on: uname -a Linux centos 3.10.0-514.el7.x86_64 #1 SMP Tue Nov 22 16:42:41 ...
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9 votes

difference tun/tap, is the interfaces that handle protocols or the OS?

The essential difference between TUN and TAP is the OSI layer at which they function (That does not include the programming required for each type of device): TAP (OSI Layer 2) - Name TAP is from to ...
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9 votes

DHCP release and renew over SSH?

The dhclient -r may work, if the DHCP server honours it and clears the lease server side. The problem is that you did it manually and lost the connection and control of the session. You had to do ...
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9 votes
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Internet not working without gpu installed?

Your networking devices are renamed to correspond with their location on the PCI bus. When you removed your GPU, your ethernet device changed from enp2s0 to enp1s0. In order to reconnect, you have a ...
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9 votes
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The difference between ip link down and physical link absence

There are difference between an interface which is administratively up but disconnected or administratively down. Disconnected The interface gets a carrier down status. Its proper handling might ...
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8 votes

Transfer files between Windows and Linux machines?

Please do not get discouraged by the overwhelming amount of information in setting up of samba. It's pretty simple as discussed here. If you do not believe, these are the steps I did in my machine ...
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8 votes

How to have two network interfaces wifi and ethernet (as a backup) working together

I would use device bonding, meaning you are creating a new virtual device for which you assign the network settings (e.g. IP address, mask, etc.) and then you enslave both the ethernet and wifi ...
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8 votes
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Remove SOME advertised link modes with ethtool

The thing with autonegotiation is that if you turn it off from one end, the other side can detect the speed but not the duplex mode, which defaults to half. Then you get a duplex mismatch, which is ...
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8 votes

Naming convention standard for Ethernet and Wi-Fi interfaces on Linux machines

The naming convention is that LAN interfaces are named eth0, eth1, ... and that WLAN interfaces are named wlan0, wlan1, ... What you see are the so called "predictable names" that systemd introduced. ...
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7 votes
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Bonds vs. Aggregators

Yes, given the following config: .-----------. .-----------. | Switch1 | | Switch2 | '-=-------=-' '-=-------=-' | | | | | | | | .-=----.--=---.---=--...
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