Unix and Linux Stack Exchange
Unix and Linux Stack Exchange

Questions tagged [loopback]

This tag is for questions about loopback interfaces on network devices. For instance, you want to configure routing on your layer 3 switch and for that you want to configure a loopback interface.

This tag is for questions about loopback interfaces on network devices. For instance, you want to configure routing on your layer 3 switch and for that you want to configure a loopback interface.

52 questions
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4 answers

Is it possible to put a real IP on a loopback device?

Is it possible to put a real IP (not in the 127.x.x.x) range on a loopback device?
Peter Smit
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How come one can successfully ping 127.0.0.2 on Linux?

On a FreeBSD system with a loopback network interface … % ifconfig lo0 lo0 link up loopback drv_running running multicast nd6 performnud auto_linklocal no_radr link rxcsum txcsum hwcsum rxcsum_ipv6 txcsum_ipv6 link address …
JdeBP
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9
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2 answers

OpenBSD: Defining a new loopback interface

I need one more loopback interface in my OpenBSD 6.1, with the IP address 127.0.0.2. I can create it by hand with the command: ifconfig lo1 127.0.0.2 And to have it at boot time, I just inserted that command into /etc/rc.local. I have researched…
Rui F Ribeiro
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why `nmap 192.168.1.97` returns less services than `nmap 127.0.0.1`?

According to https://networkengineering.stackexchange.com/a/57909/, a packet sent to 192.168.1.97 "doesn't leave the host but is treated like a packet received from the network, addressed to 192.168.1.97." So same as sending a packet to loop back…
Tim
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4
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1 answer

Why does tc-netem on loopback also affects other interfaces?

I'm trying to modify the network behaviour of my server(s), to simulate external/WAN connection behaviours (what ever that means). After doing tc qdisc add dev lo root netem delay 100ms, I can successfully add 100ms delay to all traffic from (and…
renyuneyun
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4
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2 answers

Second loopback network interface (for netem)

I would like to add a second loopback network device on Linux, so that I have lo and (e.g.) lo2. This is so that I can use netem to simulate a throttled network over lo2 without compromising my standard loopback interface. Note that I can not use an…
Paul Cager
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2 answers

How is the loopback network interface implemented?

The loopback network interface "is a virtual network device implemented entirely in software," according to another question on Unix.SE. But how is this implementation actually accomplished, and how do you manipulate it? As far as I know, IPs are…
user22602
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3
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2 answers

Manipulate filesystem image files without loopback devices?

I am trying to automate the creation of Raspberry Pi images under Docker virtual machine to run it in common CI systems like bitbucket-pipelines. On physical system I am using "template" image, mount it't partitions to local directories, then…
Dims
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2
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ipv6 multicast fails when it should loop back to self

So far I use multicast with ipv4 and it works; all involved computers run linux. I listen on two machines and send on one of those two (in a separate terminal). In the below example 'Hello 1' is received on the sending machine (strawberry) and on…
Al_
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Virtual ALSA device, sync / intercept volume commands

I have a stereo. I like it, because the sound is nice, but it's not quite sophisticated engineered: It has an internal USB Card soldered on some board, directly outputting audio to the power amp. Well.. both devices, the USB card and the power amp…
dersimn
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selinux restorecon on systems without selinux like ubuntu

recently i had to change two files on a fedora raw image mounted via loopback on ubuntu, which usually runs in a kvm on the ubuntu host. That made a lot of troubles with selinux after booting from the image because of wrong selinux labelling, the…
Mandragor
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ssh port forwarding, who has access to localhost?

I've done an ssh remote port forwarding: [email protected]% ssh -R 127.0.0.1:11999:host2.a.com:99 [email protected] My understanding is that this creates a TCP socket on host3.b.com's localhost port 11999. I then checked that from host3.b.com I can indeed…
Wandering Logic
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My computer resolves itself to 127.0.0.1 instead of its outer ip

I recently installed dnsmasq in two of my machines. The service works all right but the trouble is that when consulted they return only their loopback ip. @Machina ~]$ nslookup continua continua Server: continua Address: 192.168.1.2#53 Name:…
Lerian Acosenossa
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dummy_hcd loopback webcam. Impossible?

I've been trying to create a loopback USB Webcam device with the help of dummy_hcd kernel module. Steps I've taken: I load libcomposite via modprobe libcomposite. Then I load dummy_hcd via modprobe dummy_hcd. This creates a software-emulated UDC…
winwin
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How to make a loopback device writable for normal user?

I setup a loopback device following this guide. The device is OK, but only writable for root. I searched solutions and found some answer such as using fusermount, fstab etc., e.g. this one. I would like to know specifically: Requiring root to…
xrfang
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