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Questions tagged [ifconfig]

ifconfig is a system administration utility in Unix-like operating systems to configure, control, and query TCP/IP network interface parameters from a command line interface (CLI) or in system configuration scripts.

ifconfig (short for interface configuration) is a system administration utility in Unix-like operating systems to configure, control, and query TCP/IP network interface parameters from a command line interface (CLI) or in system configuration scripts. Ifconfig originally appeared in 4.2BSD as part of the BSD TCP/IP suite.

Source: Wikipedia.

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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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How to get TX/RX bytes without ifconfig?

Since ifconfig is apparently being deprecated in major Linux distributions, I thought I'd learn something about the ip tool that's supposed to be used instead of ifconfig. And here I ran into a problem: when run on its own, ifconfig shows the…
justinas
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Where is the statement of deprecation of ifconfig (on linux)?

A lot of people is stating that the ifconfig command is deprecated in favor of the ipone (on linux at least). This is often used as an argumentation to switch from ifconfig to ip (see some comment and answer of Should I quit using Ifconfig?). Where…
Bruno BEAUFILS
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ifconfig eth0 RX dropped packets

The problem The ifconfig command shows more and more dropped packets in the RX section. So, there seem to be a problem to some packets arriving from the Internet to my server. The questions What kind of packets does this drop counter takes into…
Fox
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CentOS ifcfg-eth0 config file deleted. Utility to recreate it?

On CentOS I no longer have a ifcfg-eth0 configuration file (I deleted it). When I run system-configure-network it shows no interfaces that I can edit. How can I recreate the ifcfg-eth0 configuration file? (Like the CentOS installer does) I can…
unixman83
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Exact meaning of RX 'errors' and 'frame' in ifconfig output?

I'm seeing network problems with a (RHEL) node (packets dropped), which also seem to manifest themselves by a non-zero count of the 'error' and 'frame' fields in ifconfig output: eth2 Link encap:Ethernet HWaddr xx:xx:xx:xx:xx:xx …
Andre Holzner
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ifconfig shows UP while ip link shows DOWN

I am looking at the state of an interface on a Linux system. When I use the ifconfig command it shows that the link is UP. master $ ifconfig docker0 docker0 Link encap:Ethernet HWaddr 02:42:b9:25:be:2d inet addr:172.18.0.1 …
automationcoach
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What is, and what problems result in a 'carrier error'

I haven't found a really clear definition about what a 'carrier error' is within the context of the ifconfig output for a interface. I have been searching on Google and there really isn't a great definition, or list of issues that cause this. I am…
Zoredache
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Get the interface and ip address used to connect to a specific host (ip)

I'm sure this has been asked and answered before, but I wasn't able to find it, so hopefully this will at least link someone to the right place. I want to find out my local interface and ip address used to reach a certain host. For instance, if I…
umop
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ip link set not assigning IP Address but ifup does

Since ip is set to replace ifconfig, I'm trying to get myself used to using the ip suite of commands. I'm trying to enable my NIC with ip link set eth3 up That doesn't assign an IPv4 address correctly. However, if I run ifup eth3 it works…
chizou
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What is the local routing table used for?

I am trying to understand what is the local routing table. If I add a random address in it with the following command: sudo ip route add to local dev Now I can ping this address, but no interface listed by…
Lilás
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Change netmask (but not ip) of network interface

The ifconfig command can change both the ip address and netmask of a network interface: ifconfig eth0 10.10.10.10 netmask 255.255.255.0 Is it possible to change the netmask of the network interface eth0 without knowing (and changing) it's ip…
Randomblue
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Correct way of bringing network interface down in linux

For example: $ ifconfig dummy0 up $ ifconfig dummy0 "192.168.1.190 netmask 255.255.255.0" Calling ifconfig with no parameters shows the interface dummy0 Link encap:Ethernet HWaddr b6:1f:f3:92:6d:20 inet addr:192.168.1.190 …
Karolis T.
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RTNETLINK answers: Invalid argument

When my system boots up it shows the following message. Bringing up loopback interface: [ OK ] Bringing up interface eth0: RTNETLINK answers: Invalid argument [ OK ] Bringing up interface eth1: RTNETLINK answers: Invalid argument [ OK …
LinuxPenseur
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What does ifconfig promisc mode do, or promiscuous mode in general?

This is what man ifconfig has to say about it. [-]promisc Enable or disable the promiscuous mode of the interface. If selected, all packets on the network will be received by the interface. Looking for specifically if this means in regards…
Evan Carroll
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