Unix and Linux Stack Exchange
Unix and Linux Stack Exchange

Questions tagged [interface]

123 questions
184
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4 answers

Good detailed explanation of /etc/network/interfaces syntax?

I understood the very basic concept of how to use /etc/network/interfaces, but all I find online are examples, example after example, which I can copy-paste from. What I miss is an explanation of the syntax, an explanation of the meaning of the…
Foo Bar
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11 answers

How to use ifconfig to show active interface only

By default ifconfig will show me all available interfaces , but what if I just want to display active ones? Like, en0 only in below. en0: flags=8863 mtu 1500 ether 14:10:9f:e0:eb:c9 inet6…
qweruiop
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3 answers

Change Mac Address permanently inside /etc/network/interfaces

QUESTION: How might I be able to specifically change the Mac Address of the enp3s0 and wlp2s0 interfaces through the /etc/network/interfaces file? What code would I have to include inside? I have been trying for some time now without success sadly…
Webeng
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What are the interface prefix meanings in ifconfig?

I'm not sure if these have a name, but on most computers I use the interface prefixes are usually: eth- : Ethernet/Wired wlan- : Wireless/WiFi However, on my ASUS RT-N56U, I have the following: br0 : 'Ethernet' - Bridge? eth2 : 'Ethernet', IPv6…
Ehryk
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/etc/network/interfaces - difference between auto and allow-hotplug

I am running Debian 9.13. I tried to check what is the difference between auto eth1 and allow-hotplug eth1 in /etc/network/interfaces. I have eth1 networking interface connected via USB. I tried rebooting, running systemctl restart networking and…
Jędrzej Dudkiewicz
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1 answer

How do I force ssh to use a second interface with higher metric?

I have a Crunchbang VM with two interfaces, eth0 and eth1, each of which connects to an OpenWRT VM (eth0 being 10.232.64.20 and eth1 being 10.232.65.20). I'm using Network Manager and DHCP. My overall goal is having multiple ssh connections, and…
mirimir
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1 answer

What does "if1@if2" mean in interface name in output of "ip address" command on Ubuntu

What does at sign (@) mean in interface name in output of "ip address" command (or the "ip link" command) on Ubuntu, for example interface name "eth0@if44" in the following output: root@aafa1fc24a0b:/# ip address 1: lo: mtu…
Bruno Rijsman
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1 answer

How to find out the number of network interfaces available in a linux system?

I need to loop over the network interfaces available in Linux. I'm interested in all kinds of interfaces (loopback, ethernet, vlan, bridge) - whatever shows up in ifconfig -a. Is there a way to enumerate the interfaces in Linux? By any command or by…
user1762571
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What does lo in iptables mean exactly?

I have seen countless examples of this rule in iptables: -A INPUT -i lo -j ACCEPT I thought lo means localhost (a.k.a. 127.0.0.1), but when I commented it out, I can't access the server using its private ip address 192.168.1.3, which means it is…
Question Overflow
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How do I set up several interfaces all bridged onto eth0?

I have found several guides to bridging a single interface (eg br0) onto eth0 but none for multiple interfaces (eg br0, br1 etc). Is this possible?
user12810
5
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1 answer

Difference between virtual interfaces with ifconfig and iproute2

I am wondering what is the difference between: # ifconfig eth0:0 1.1.1.1/24 and just # ip addr add 1.1.1.1/24 dev eth0 Btw I cannot do # ip addr add 1.1.1.1/24 dev eth0:0 RTNETLINK answers: File exists In ip addr show it appears differently…
little-dude
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Network naming on Arch Linux

I've just installed Arch Linux on my old PC, to do the installation I used wifi-menu wlan0, now I've reboot but if I type: ifconfig wlan0 up I have as a result: wlan0: ERROR while getting interface flag: no such device I read that after the…
Mitro
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Where does ethtool get information from?

When I run the command ethtool -S wlp2s0, I get the following information: NIC statistics: rx_packets: 63 rx_bytes: 14163 rx_duplicates: 2 rx_fragments: 58 rx_dropped: 30 tx_packets: 60 tx_bytes: 9668 …
imll
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setting firewall-cmd --permanent is not sticking after reboot

I have two network interfaces: eth0, and p2p1. My default zone is set to public. I would like to permanently set p2p1 to be trusted. In order the achieve this I run: sudo firewall-cmd --permanent --change-zone=p2p1 --zone=trusted after that I get…
MeSo2
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Using ip, what does M-DOWN mean?

When using the terminal tool ip, there is a number of flags for every interface. Example: eth0: mtu 1500 qdisc noqueue What is the meaning of M-DOWN? What command to be used to make it up or down?
R_SS
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