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Questions tagged [loopback]

In TCP/IP a loopback device is a virtual network interface implemented in software only and not connected to any hardware, but which is fully integrated into the computer system's internal network infrastructure. Any traffic that a computer program sends to the loopback interface is immediately received on the same interface.

In TCP/IP a loopback device is a virtual network interface implemented in software only and not connected to any hardware, but which is fully integrated into the computer system's internal network infrastructure. Any traffic that a computer program sends to the loopback interface is immediately received on the same interface.

A loopback interface has several uses. It may be used by network client software on a computer to communicate with server software on the same computer, namely on a computer running a web server, pointing a web browser to the URLs http://127.0.0.1/ or http://localhost/ will access that computer's own web site. This works without any actual network connection–so it is useful for testing services without exposing them to security risks from remote network access. Likewise, pinging the loopback interface is a basic test of the functionality of the IP stack in the operating system.

Source: wikipedia

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iptables redirect local connections to remote system / port

I am trying to use SSH to port forward windows machines local port 3389 to a redhat server on some arbitrary port (in the unprivileged region) I have protected behind a firewall, then forward the unprivileged port on the redhat server onto the users…
dynamphorous
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No network loopback device after security update ubuntu 12.04

I've had Ubuntu 12.04 on a server for the last several months, with everything working fine. Last night I did an aptitude update && aptitude safe-upgrade to bring in all the latest security changes, and now when I boot the server no lo device is…
quangdog
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How can I copy a LVM logical volume to a loopback file on another system?

I am trying to copy an LVM logical volume with an ext3 filesystem from one system to a file on another system that I will be able to mount as a loopback device. I have tried the following command to copy the volume: dd…
Dave Forgac
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How do I mount an .iso with another (live CD) .iso?

I want to: Place the .iso of a live CD in a directory. Use qemu (kvm or kqemu) to run the .iso Put a 2nd live CD .iso in the same directory. Have the 1st live CD mount the 2nd .iso. Say, I have 2 .iso files in the same directory, how can I emulate…
None
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Forwarding a port on the loopback interface to a remote IP/port

I have two Docker containers that I'm trying to network together in a specific way. Container A is running a Redis server on port 6379. Container B is running an interactive shell and needs to access Redis. Using Docker's linking feature, a user…
Jimmy
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Virtual PC (XPMode) - Setting up Loopback Adapter for guest to talk to host

I have Windows XP running inside Windows 7 via Virtual PC (XPMode). Now I want the IE6 browser inside the virtual XP guest instance to be able to talk to the IIS webserver running in the host OS (Windows 7 IIS 7.5). I understand I need to setup a…
Sunday Ironfoot
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How do you NAT Hairpin in IOS 8.3+

As I asked here and duplicated here it appears NAT Hairpinning is the answer I'm looking for to allow internal servers to loopback through the ASA to access external IP's (without using DNS Doctoring). However, the instructions presented in those…
Novox
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Loopback to directory

How do I create a loopback mount which exposes a given directory as a read-only filesystem? As contrasted with a loopback mount which exposes a file as a filesystem?
Avdi
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How to enable HTTP loopback connections?

I running CentOS release 5.8 (Final) for my WordPress blog (deluxeblogtips.com). I have a backup plugin BackupBuddy, and it says: HTTP Loopback Connections are not enabled on this server After some tries on Google, I found some solutions, but none…
Anh Tran
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What is the Microsoft Loopback Adapter used for?

Why is Microsoft Loopback interface called _loopback_ inteface? RFC3330 states that a loopback interface is an interface with an IP address in the 127.0.0.0/8 address range. Yet, when I enter the 127.x.x.x address in Microsoft Loopback TCP/IP…
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Can you ping a Cisco Router's Loopback Interface from a PC using PacketTracer

I may be misunderstanding what you can do with a Router's loopback interface. I am trying to ping it from a PC on the same network. I am using Packet Tracer to simulate this, a Cisco 1841 and a PC from within the program. IPs Cisco 1841: interface…
Jim
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Loopback interface on Linux catches all loopback traffic

On a linux machine with a normal loopback interface: $ ifconfig lo lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 …
Matthew Buckett
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Disable ipv6 loopback

I am trying to get the IPv6 loopback completely disabled/disconnected. Searching the posts here I see everything that I have done so far. 1)Un-check the IPv6 on the adapter which will disable IPv6 for that LAN interface. 2)Add the…
Chadddada
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Viewing the loopback interface on Solaris 10 (using snoop or another tool)

I am trying to use snoop on solaris 10 to detect traffic between a client and server both located on my machine. Question: I just want to verify that I should use the loopback interface for this. So now for the real question. I have found a few…
sixtyfootersdude
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Add-NetNatStaticMapping not port forwarding to local VM

I'm running windows 10 build 1809 and have hyper-v installed. I have a Linux machine running behind a NAT with internet connectivity working on IP 10.0.5.5. I basically followed instructions on the link…
Mark
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