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.
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Why does my hostname appear with the address 127.0.1.1 rather than 127.0.0.1 in /etc/hosts?
This may be a bit of a noobish question, but I was taking a look at /etc/hosts on my new Xubuntu install and saw this:
127.0.0.1 localhost
127.0.1.1 myhostname
On most 'nixes I've used, the second ...
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How fast is 127.0.0.1?
I wonder if it is tied to my NIC at all or if the OS or driver intercepts and immediately returns data sent to the loopback address?
Does the signal actually travel to my NIC then the NIC returns it?
user55029
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What is the rest of the 127.0.0.0/8 address space used for?
We all know what 127.0.0.1 is used for (loopback).
What are uses cases for the rest of the reserved 127.0.0.0/8 loopback space?
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Mount block file on OSX
How can block files be mounted on osx? I tried
hdiutil attach filename
however this is terminating with
hdiutil: attach failed - not recognized
hdiutil only seems to work for iso/dmg images. On ...
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IPv6 Loopback Addresses (equivalent to 127.x.x.x)
I have a development environment set up where I have a separate loopback address for multiple websites.
For example, I have the following:
127.0.0.1 www.example.com
127.0.0.2 foo.example.com
127.0.0....
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iptables rules to allow HTTP traffic to one domain only
I need to configure my machine as to allow HTTP traffic to/from serverfault.com only. All other websites, services ports are not accessible. I came up with these iptables rules:
#drop everything
...
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Make apache only accessible via 127.0.0.1, is this possible?
I've set up my Apache server, and the PHP/MySQL works well!
But the issue is, how do I keep this private, since it's a development-only server?
The only reason for keeping the content private is if a ...
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Disable IPv6 on Loopback address (Localhost, Computer name, ...)
We tried installing a 3rd party software product on a new Windows Server 2008 R2 machine and found that everything works except for accessing local services through loopback addresses such as ...
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Concatenating files to a virtual file on Linux
On a Linux system, is there any way to concatenate a series of files into one exposed file for reading and writing while not actually taking up another N bytes of disk space? I was hoping for ...
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Why only a single loopback address on IPv6?
IPv4 allocates a whole block of IPv4 loopback addresses, 127.0.0.0/8. IPv6, in contrast, only allocates a single loopback address, ::1.
This seems surprising that IPv6 would be so stingy in its ...
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Why can't I ping an address on the loopback device under FreeBSD?
From Wikipedia:
The most commonly used IP address on the loopback device is 127.0.0.1
for IPv4, although any address in the range 127.0.0.0 to
127.255.255.255 is mapped to it.
This is not true,...
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How to mount an ISO file in Linux?
I have just created ISO using these instructions:
Creating an iso file in Linux
How can I mount this iso image that was created?
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ssh -R binds to 127.0.0.1 only on remote
I'm running ssh -N -f -R127.0.2.3:23000:127.1.2.3:23000 user@remote , and I expect the tunnel on remote has opened on 127.0.2.3:23000, but it only opens on 127.0.0.1:23000, and it's inconvenient ...
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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 ...
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Curl request wont resolve to localhost
I have an ubuntu server running apache on localhost / port 80. It's domain is sub.domain.com
If I make a curl request to http://localhost on that machine it will error with 'couldnt connect to host' ...
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Vista Power Management GPO
I've created a loopback GPO that has several settings (both computer and user) including a Custom User Interface (Access 2007 Application) and Power Management (has the computer sleep after being idle ...
user9573
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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 ...
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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 ...
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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?
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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 ....
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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 ...
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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 ...
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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)....
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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 ...
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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 (...
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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
...
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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 ...
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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 ...
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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 ...
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How do I force localhost resolution to be 127.0.0.1 instead of ::1?
I'm running Windows 10 x64 and I have a legacy application that doens't work fine with localhost being translated to ::1, but instead it works for 127.0.0.1.
How do I force Windows 10 to resolve ...
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Heavy TCP traffic on loopback
While trying to generate some test traffic on my loopback interface, I noticed there was so much noise there that the output from Wireshark was essentially useless, with tons of SYN/RST, ACK packets ...
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DRBD on a file (rather than partition)
We have a number of Xen virtual machines that use disk image files.
disk = ["file:/xen/vbd/something.vbd,sda1,w"]
We'd like to use DRBD to replicate these files for backup (as opposed to the mess of ...
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Is it important to use localhost/127.0.0.1 rather than machine's own IP address?
I'm on Amazon AWS EC2 running Amazon Linux, though that may not be significant to the answer.
Say I have three hosts, H1, H2, H3, with private IP addresses of 10.0.0.1, 10.0.0.2, and 10.0.0.3. This ...
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How can I give access to loopback devices which are created dynamically to a Docker container?
I have a small Docker container from which I can access /dev/loop0. For this I've added to docker run:
--device=/dev/loop-control:/dev/loop-control \
--device=/dev/loop0:/dev/loop0 \
On this ...
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Is there a security downside to having iptables ignore the loopback interface?
I have the following rules in my iptables (I cut out the rules that aren't relevant to this question):
*raw
:PREROUTING ACCEPT
:OUTPUT ACCEPT
-A PREROUTING -i lo -j NOTRACK
-A OUTPUT -o lo -j ...
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Configuring a loopback interface on a Cisco router
I have Router 1 with the following interfaces:
FA0/1: 192.168.9.193 255.255.255.224
S0/0/0: 192.168.9.129 255.255.255.224
S0/0/1: 192.168.9.161 255.255.255.224
This is for my assignment at ...
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Centos 7.1 Create Loopback Interface [duplicate]
I'm trying to alias an ip address onto Lo or create a new loopback interface such as lo:1
I've created /etc/sysconfig/network-scripts/ifcfg-lo:10
DEVICE=lo:10
IPADDR=192.168.10.1
NETMASK=255.255.255....
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Loopback Processing Merge Mode
I am part of a team of IT Engineers who are currently revamping a large organisation.
The previous IT department had some Group Policy objects in place for installing software(s), applying security ...
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Monitor loopback traffic (monitor MS TCP Loopback inteface traffic) with Microsoft Network Monitor 3.4 - possible?
I've downloaded NM 3.4 from microsoft.com and it appears that the software doesn't capture traffic on MS TCP Loopback interface. When I ping 127.0.0.1 address, NM shows no packets flowing. I've tried ...
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How to setup loopbackon my Windows Server 2008 Virtual PC VM?
I am trying to setup a virtual sharepoint environment for development and need to be able to access my sharepoint sites on my host machine. From hours of google research, I discern that I must setup ...
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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 ...
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Why is the loopback device needed on a client side of Stunnel?
This SANS Institute guide states that
"On the client side, a port listening on the loopback interface of the
local system would send/receive data on the clear-text protocol and
tunnel out on ...
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IP Address is very slow compared to loopback address
I have an AWS EC2 VM. I want to run a bunch of scripts on a PostgreSQL server hosted on the same machine. When I use the IP address of the server in scripts, it took almost 5 seconds per script. But ...
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Is it okay to copy an image file which is still mounted via a loop device?
I have a 100 GB image file which is created using dd. This image file is mounted via a loop device as read-write.
I want to store a backup of this image file at a remote location. I have a script ...
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What is the difference between Loopback Interface and Dummy Interface in Ubuntu 20.04
I would like to know whats the differences between loopback and dummy interfaces in Ubuntu and how they behave.
Because when I assign /24 IP address on Loopback interface and route this range in my ...
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Adding a virtual NIC to a 2008R2 server makes internet unreachable, why?
I currently have a Windows Server 2008R2 box with a single physical NIC. For what I want to do I need two network adaptors in the box. To accomplish this, I added a legacy hardware device "Network ...
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What is the proper position for the loopback address in a DNS server selection list?
Best practices indicate that one should list 127.0.0.1 in the DNS list for the network adapter configuration for a Domain Controller, but not as the first one. With that said, what is the best place ...
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HP switch 'mirror port' makes a Cisco switch port err-disabled due to keepalive loop-back
I'm trying to connect an HP ProCurve 5304xl switch to a Cisco 2950. The HP port I'm connecting to is described as a 'mirror port', which appears to be like a SPAN port except that it also allows ...
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Bandwidth limitations of network loopback device?
I have several JVMs that all listen to TCP 80 each bound on their own 127.0.100.1 -> 127.0.100.255 range.
Is there a theoretical limit to the effective bandwidth that can be pushed through the LO ...
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Gigabit RJ45 loopback not working (100 Mbps ok)
I made myself a loop back plug as per
When I plug it into a 1Gbps port on 100/1G switch the port does not light up.
100 Mbps port on 100 Mbps switch lights up no problem.
The obvious problem could ...
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