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.
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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 ...
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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 ...
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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 ...
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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 ...
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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 ...
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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:...
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1
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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:...
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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 ...
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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 ...
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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 ...
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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 <any-ip-address> dev <network interface>
...
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9
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3
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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 ...
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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:...
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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 ...
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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: ...
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How can I reset the statistics reported by ifconfig?
I'm trying to trace a possible link problem on one of our servers' ethernet interfaces. ifconfig reports a large number of error packets. I've asked the hosting company to make some changes to the ...
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How to add a broadcast address to loopback with ifconfig on a OS/X?
I am trying to use ifconfig to turn on broadcast on my loopback interface. It currently reads:
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 16384
As you can see, no broadcast address! :( ...
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2
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How can I list all virtual networks for a given network interface in linux?
How do I list all virtual networks created for a given network interface card?
E.g. I have added a virtual network like this,
ifconfig eth0:0 inet6 add ::123/64
It's responding fine. And I know I ...
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IP served by OpenVPN doesn't take ipp.txt into account
I'm facing some troubles right now with an OpenVPN server an former colleague set up (I'm not too into it ATM). We're using OpenVPN for a private network of ~200 clients (to be more specific, only 15 ...
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4
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Server answers only on one IP. Why?
ifconfig -a
eth0 Link encap:Ethernet HWaddr 00:25:90:60:1B:FC
inet addr:10.0.47.42 Bcast:10.255.255.255 Mask:255.255.255.248
inet6 addr: fe80::225:90ff:fe60:1bfc/64 ...
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How to list all the ip addresses of a server
When I type ifconfig, I see that my server has an new ip address each day. The ip addresses belong to a set of ip addresses.
How do I find out all the ip addresses of my server?
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ifconfig showing wrong RX/TX byte count
ifconfig tells for eth0 some RX = 2,8GB, TX = 1,3GB value that cannot be real, since I recently transmitted many 10GB+ files over eth0. I would like to know
if that's just some ordinary integer ...
nils
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1
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Is "inet addr" my or "bcast" my machine's actual IP? [closed]
I'm trying to connect from one machine to the other (for Postgres), and I'm confused about how to configure my IP address, both from a allow connections from IP address X and from a connect to machine ...
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What does RUNNING in ifconfig output mean?
Does anyone know what the RUNNING flag in ifconfig output means? (I don't know that it matters much, but this is on a Solaris 10 box.)
The only thing I've been able to find on it so far is this ...
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3
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Why does ifconfig reset the default gateway route?
In FreeBSD, an ifconfig call seems to delete the default gateway route, even when given the same IP-address (e.g. when updating the netmask only). Is it a bug or a feature?
As fas as I remember Linux ...
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Privileges for ifconfig
In order to do ifconfig in Linux and change the IP and VIP does it require root privileges?
Or it is also possible to do this via a non-root account?
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BASH script that tests for IP
Is there an elegant way to test an IP address in a BASH script? I could do ifconfig and narrow down the IP using sed/awk, but I think there is a simpler solution.
My application is basically using ...
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Portable way to get list of all active network interfaces
I would like to get the list of all active network interfaces (e.g. eth0, wlan0). I assume I'll have to parse the output of ifconfig, but the formatting is different across the various OS's. Does ...
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No outbound internet connection after restarting CentOS 6.3
After restarting a headless CentOS 6.3 machine, it lost outbound internet connectivity, i.e. I can still connect to the server via SSH (ssh root@**.126.18.56), but stuff such as ping google.com gives ...
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FreeBSD 11 not showing RX,TX packets and counts
I am having a FreeBSD 11 system in which I get the following output for ifconfig command
# ifconfig
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> metric 0 mtu 16384
options=600003<...
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LVS-TUN: ifconfig shows errors and collisions for tunl0 interface?
Check_MK has sent me an email as follows:
***** Nagios *****
Notification Type: PROBLEM
Service: Interface 5
Host: foo
Address: x.y.z.t
State: CRITICAL
Date/Time: Fri May 3 10:02:40 ICT 2013
...
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ifconfig maximum value of RX/TX bytes
I have a server with over a year uptime which shows 9 TIB outgoing traffic.
I was wondering how accurate this number really is?
It's running linux 2.6.32 kernel.
What I would also like to know that ...
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Debian - static ip, /etc/network/interfaces
I tried to set a static IP on my Debian 8.1 (in VirtualBox), so I edited the /etc/network/interface file :
# The loopback network interface
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet ...
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4
votes
1
answer
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Strange ifup/ifdown behaviour on Debian Lenny
First of all, here is my /etc/network/interfaces
auto lo
iface lo inet loopback
auto eth0
iface eth0 inet static
address 10.10.4.142
netmask 255.255.255.0
gateway 10.10.4.1
auto eth1
iface ...
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1
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How do I add a broadcast IP to the loopback interface under os/x using ifconfig when my machine has no network? [duplicate]
I'm new to advanced network administration and I would like to do some testing with UDP broadcasting, so I need a broadcast address on my loopback interface. The machine is offline, in other words, ...
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Ifconfig Alias Address Assigned by DHCP
I would like to create several aliases to eth0, but have the addresses assigned by DHCP instead of being set to static IP's. Is this even possible?
All the examples I've seen assign a static IP ...
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Difference between ip link eth down and ip link dev eth down
What's the difference between ip link set eth0 down and ip link set dev eth0 down ?
The difference between the commands does not appear to be documented anywhere.
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Configure static IPv6 on Ubuntu
I'm trying to configure IPv6 on a dedicated Ubuntu server. My provider gave me a "/64" (whatever that is - I'm still confused) of IPv6 addresses.
However, when I try to use them, I can't ping ...
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FreeBSD 8.0 "Watchdog Timeout" drops ethernet connection
Recently my FreeBSD 8.0 (GENERIC) box was hit with a large amount of requests from an IP in Taiwan, trying to guess passwords and all of that stuff. Anyway, long story short, I noticed at a certain ...
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What does the command "ifconfig <interface> 0.0.0.0" do? [closed]
The question is direct, what does the given command do, and what is it used for?
ifconfig <interface-name> 0.0.0.0
I know that 0.0.0.0 means all IP addresses on my local machine.
Also if I ...
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Track Source IP of dropped packets
I've got a Linux server running CentOS 7, and I've been facing an issue where the RX dropped packet count keeps increasing. I believe it may be caused by a faulty cable/connector in the network; ...
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2
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How to set the order of ipv6?
an output on my server shows IPv6 in the following order:
inet6 addr: 2xxx:xxx:aaac:3e::10/48 Scope:Global
inet6 addr: 2xxx:xxx:aaac:3e::1/48 Scope:Global
inet6 addr: 2xxx:xxx:aaac:3e::2/48 ...
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What initiates parsing of the /etc/sysconfig/network-scripts/ifcfg-* interface scripts?
I have been searching for a while and looking at source code and various scripts on the Linux filesystem and still have been unable to figure out what ultimately initiates the reading of the scripts ...
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Why can I listen on an IP not listed by ifconfig?
I'm putting my hands on a legacy system (a Xen cluster) and I'm trying to understand its architecture. It seems that there are services listening on an IP (say, 1.2.3.4) that doesn't show up in ...
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Granting user enough privileges to run ifconfig on IllumOS (OmniOS)
I sense this should be a very simple question, but somehow I cannot find a solution.
I have a non-root user and I would like to grant this user enough permissions or privileges, so he can run ...
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How to make my linux vm attach to an openvswitch bridge?
I am following this tutorial: http://networkstatic.net/wp-content/uploads/2012/04/openvswitch.openflow.gre_.tutorial1.pdf
In brief: br0 is connected to the actual net, br1 is an isolated bridge to ...
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Routing OpenVPN tunnel in via public interface and out via NAT'd interface (to internet)
I hope someone can help...
I want to Configure OpenVPN-AS (i.e. OpenVPN Access Server, NOT OpenVPN) to work on my VPS. The VPS is a KVM running Ubunto 10.04 LTS, with a very vanilla configuration. ...
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1
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Find number of TCP bytes transmitted
I have rhel4 and rhel6 hosts.
I can use netstat -s to see information on the number of segments sent/received. I can use ifconfig to see the number of bytes sent/received on a given interface (for ...
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1
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With CentOS 6 and LXC, "ifconfig" is unable to see network interface (but busybox "ifconfig" works fine)
I've just started working with LXC under CentOS 6 (via the libvirt adapter). If I create an LXC container, I'm unable to see any network interfaces when using the native system tools:
# ifconfig -a
#...
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3
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0
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ifconfig output different for non-root user
we use a montoring system to capture network traffic. the output as root user is fine:
eth0 Link encap:Ethernet HWaddr 00:1E:67:E6:D6:FE
inet addr:149.56.19.13 Bcast:149.56.19.255 ...
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