Unix and Linux Stack Exchange
Unix and Linux Stack Exchange

Questions tagged [iproute]

Questions that include employing tools of the IPROUTE2 Utility Suite, especially ip and tc.

285 questions
105
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3 answers

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

I have a Dell XPS 13 ultrabook which has a wifi nic, but no physical ethernet nic (wlan0, but no eth0). I need to create a virtual adapter for using Vagrant with NFS, but am finding that the typical ifup eth0:1... fails with ignoring unknown…
STW
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102
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7 answers

List ports a process PID is listening on (preferably using iproute2 tools)?

I'm looking to list all ports a PID is currently listening on. How would you recommend I get this kind of data about a process?
ThorSummoner
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47
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2 answers

How can I bridge two interfaces with ip/iproute2?

I know how to create a bridge using brctl, but I have been advised not to use this anymore, and to use iproute2 or ip instead(since brctl is deprecated presumably). Assuming this is good advice, how do I create a bridge using ip? For instance, say I…
Totem
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43
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3 answers

alternative to "netstat -s"

netstat -s prints out a lot of very detailed protocol statistics like number of TCP reset messages received or number of ICMP "echo request" messages sent or number of packets dropped because of a missing route. When in Linux netstat is considered…
Martin
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28
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2 answers

How to understand (the output of) ifconfig or ip addr show

The ifconfig command dumps a lot of information at you, especially if you have a lot of interfaces, and you don't know where they come from. I've read through the "Ifconfig Command - Explained in Detail" tutorial page, which gives a great rundown on…
Ari Sweedler
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28
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2 answers

Is it possible to have multiple default gateways for outbound connections?

I would like to have multiple NICs (eth0 and wlan0) in the same subnet and to serve as a backup for the applications on the host if one of the NICs fail. For this reason I have created an additional routing table. This is how /etc/network/interfaces…
rosix
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25
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4 answers

Can I create a virtual ethernet interface named eth0?

I am running Arch based on the Linux 3.10.5-1 kernel. The system uses the new de-facto naming conventions of ethernet interfaces enp*s* and wlp* etc. This is a problem however, as my educational institution is using a program called Maple 17.…
Steen Schütt
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18
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1 answer

Linux as router with multiple internet providers

Linux as router: I have 3 Internet providers, each with its own modem. Provider1, which is gateway address 192.168.1.1 Connected to linux router eth1/192.168.1.2 Provider2, gateway address 192.168.2.1 Connected to linux router…
Flav
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18
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4 answers

Where is the official documentation (Debian package iproute-doc)?

Manpage of ss says: FILTER := [ state TCP-STATE ] [ EXPRESSION ] Please take a look at the official documentation (Debian package iproute-doc) for details regarding filters. What does that mean? I can't find anything under…
Tim
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16
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4 answers

'ip addr' command shows 'UP' even there is no address associated with that interface

I would like to understand what is meant by an network interface up? Because ip addr or ifconfig command shows an interface as up even when there is no IP associated with it. for example on RHEL7 : [root@IDCDVAM887 ~]# ifconfig ens256 ens256:…
Srikanth Ganesan
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14
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1 answer

Understanding ip route output

I am learning about Linux routing, routing tables, IP routing, etc... The following is the output from ip route followed by the output of route: default via 192.168.1.1 dev wlp0s20f3 proto dhcp metric 600 169.254.0.0/16 dev wlp0s20f3 scope link…
RhythmInk
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13
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1 answer

What's the exact behaviour of the command: ip address change?

I have been fiddling with IPv6 and address lifetimes. I found out that the valid_lft attribute will make a v6-address disappear automagically, if used correctly. To extend an address' lifetime I would ip addr change 1:2:3:4::1/112 dev eth0 valid_lft…
Bananguin
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11
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2 answers

The difference between ip link down and physical link absence

In Linux, is there any difference between after-ip link down-condition and real link absence (e.g. the switch's port burned down, or someone tripped over a wire). By difference I mean some signs in the system that can be used to distinguish these…
red0ct
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11
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4 answers

Pretty display of "ip route"

I'd like to use more of the iproute2 (ip command) utility instead of the deprecated net-tools (ifconfig, route, ...). The main reason I keep going back to net-tools is the output of ip route which in my humble opinion is lacking in clarity compared…
Gohu
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11
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Why is the default output of ss so strange?

When I run ss -tnlp to display all programs listening for tcp connections (something I do rather often) I get something like this: Despite the terminal being wide enough, ss chooses to split some lines and display the processes on the next line. I…
Patrick
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