Questions tagged [networking]

Managing and using network connectivity on a unix system

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4 views

OpenVPN bridge connected printer can't send ping reply to server

I am using wifi-connected computer set up near my non-wifi-capable printer as a bridge to put the printer within my subnet. The computer is set up as a vpn client with the tap port bridged with eth0. ...
7
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3answers
1k views

How can I specify a local port when establishing SSH connections?

I have two servers hosted in IDC. I can only use ports 20/21/22/23/3389/33101-33109 to establish connections between two servers. The IDC network device will block any other packets whose source or ...
9
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2answers
60k views

How to delete an IP route?

How to delete a route like the one below from a UNIX server? 122.252.228.38/255.255.255.255 122.252.228.38 UH 0 lan4 4136
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2answers
135 views

Change MAC address immediately after system activation

I have few computers each with same ethernet MAC address. I want to change ethernet MAC address on each computer as soon as network card is detected so I do not have any conflicts in the network. My ...
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2answers
33 views

Additional network using /etc/network/interfaces

We have network interface eno1 and configured it as br1 allow-hotplug eno1 iface eno1 inet manual auto br1 iface br1 inet static address 208.43.222.51 network 255.255.255....
9
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2answers
760 views

Why do changes to /etc/hosts take effect immediately?

Changes to /etc/hosts file seem to take effect immediately[1][2]. I'm curious about the implementation. What magic is used to achieve this feature? [1] https://askubuntu.com/questions/665995/after-...
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2answers
707 views

Connect to a wireless network as standard user without administrator authentication Linux Mint 17.3

I'm trying to get a standard user on my laptop installed with Linux Mint 17.3 on the wireless. I can get to the internet just fine logged in with an administrator but as soon as i log in with a ...
1
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1answer
19 views

Centos 7 Oracle VM - Unable ping default gateway

Update: I have configured NAT as adapter 1 and Host Only as adapter 2. However, ping default gateway (192.168.56.1) returns "Destination Host Unreachable". Any advice thanks! I am stuck for 1 week ...
3
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1answer
25k views

How to set up an usb/ethernet interface in Linux?

me@me:~$ sudo /etc/init.d/networking restart [ ok ] Restarting networking (via systemctl): networking.service. me@me:~$ sudo service network-manager restart me@me:~$ sudo ifup eno1 Internet Systems ...
1
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0answers
15 views

How to prioritize traffic using bridge and qdisc?

I'm trying to prioritize traffic over the Linux-based software bridge in my network. When I generate traffic locally (on the machine hosting the bridge), the traffic is correctly prioritized. However, ...
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2answers
27 views

Running commands on shutdown/restart Ubuntu 18.04

[My Config] Ubuntu 18.04 - digitalocean droplet/server [Background] I presume from my research that since 18.04 /etc/network/intefaces has been deprecated and something called netplan was introduced. ...
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0answers
399 views

Unable to set wifi frequency/channel on Raspbian

Hey I'm trying to configure my Raspberry Pi to connect to my router on channel 8 (2.447G). The WiFi network adapter I have for my Pi seems to be stuck on channel 1. iwlist scan only lists the one ap ...
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3answers
40k views

Change IP address of a Virtual Machine running linux ubuntu on windows 8?

I currently have created two virtual machines in VirtualBox both running linux Ubuntu 14.04, and now want to have them have different IP addresses. (By default, they have the same IP address.) However,...
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0answers
24 views

Unstable wifi/Connection drops with Qualcomm QCA9377 on Ubuntu 18.04

So I have dualboot on my Acer Aspire with Linux Lite XFCE(Ubuntu) and Windows 10. Network Controller: Qualcomm Atheros QCA9377 802.11ac A while ago I started having issues with Wifi connection ...
72
votes
8answers
104k views

Simple way to create a tunnel from one local port to another?

I have a development server, which is only accessible from 127.0.0.1:8000, not 192.168.1.x:8000. As a quick hack, is there a way to set up something to listen on another port (say, 8001) so that from ...
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0answers
17 views

Prevent Ubuntu 18.04 from registering all network adapters in dns zone except for a valid interface

Ubuntu machines have enp0s31f6 and wlp2s0 network interfaces. I have a mess in dns zone where resolving a machine name results to 172.17.0.1 or 172.18.0.1 or anything random because multiple A records ...
1
vote
1answer
44 views

Configuring Additional Failover IPs in Debian 9

How can I properly configure failover IPs in Debian 9? I tried below settings after restart /etc/init.d/networking restart new FO IPs are pingable but server goes down for upto 30 minutes. I ...
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0answers
23 views

Set up an OpenVPN server inside VirtualBox

My goal is to set up OpenVPN server on my PC as a guest in a virtual machine.  I would like to use that OpenVPN server to join my home network from anywhere. On my PC (host) machine (192.168.1.116/24) ...
19
votes
4answers
54k views

Arch Linux - connect: Network is unreachable

After five unsuccessful Arch Linux installations, I've got two that installed correctly. The first time, the network worked fine, and I was even installing Arch Linux over SSH. After booting from the ...
0
votes
1answer
19 views

Accessing the output of the Network Interface Card

I am working on a project in which I need to interface directly with the WLAN Network Interface card, i.e., using the drivers of course. It is lot like wireshark. Also, I want to send some custom ...
0
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0answers
22 views

check file of sftp and return output to log

I need your assistance. I'm trying to finish a script that I've done but it is not working perfectly. here is the script: #!/bin/bash # iclog=log key="keys/cash_prod_key" date=$(date +%Y%m%d) ...
3
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0answers
28 views

RFC4821 Path MTU discovery for IPv6 on Linux

I have configured an IPv6-over-IPv4 tunnel via Hurricane Electric on my Linux machine. While I can ping ipv6.google.com: bash-4.4# ping ipv6.google.com PING ipv6.google.com(lhr48s09-in-x0e.1e100.net (...
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0answers
27 views

Systemd: Run a command before shutdown, while network is still up

I'm trying to get Systemd to run a script that sends out an email before the computer shuts down. I understand Systemd terminates services in the reverse order they are started, so if you put After=...
1
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0answers
25 views

New loopback device module does not show trace in wireshark

I am trying to write a network device driver that can duplicate the functionality of the loopback device. I modified the code available at the link. I am testing on Linux 4.8. I removed code related ...
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2answers
1k views

IP packets have wrong source address

I have two 4G modems connecting to a network and sending and receiving data. There is a problem though, as the modems keep getting kicked off the network because the source IP address of the packets ...
1
vote
1answer
44 views

Cache all of my internet browsing?

Is it possible to generate a cache of all of my internet browsing on Linux? So, any time I visit a webpage, that page is automatically downloaded to my computer, and the next time I visit said page, ...
1
vote
2answers
173 views

How wait for eth0 interface before running “ip link”, “ip addr” and “ip route” commands?

I have the following script that I need to run on my Synology NAS at boot-up. The Synology NAS has built-in scheduled tasks with the ability to trigger tasks at boot-up. The script I need to run is ...
1
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0answers
99 views

What is an up-to-date equivalent of LARTC How-To?

The Linux Advanced Routing and Traffic Control How-To was a guide on configuring things like the quality of service modules, iptables, multicasting and IPv6. Since work stopped on it, Linux has ...
1
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1answer
35 views

Slow ethernet, fast wifi

I'm running a Lenovo Legion Y7000P with Pop OS 18.04. My ISP is AT&T. My WiFi tests at about 20Mbps down, 5Mbps up, but my ethernet-over-power set, which is rated for 600Mbps up/down, only gets ...
0
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0answers
10 views

ASA/Racoon VPN setup (FreeBSD) troubleshooting - sanity check setup

I am setting up VPN between a Cisco ASA and a freebsd server as our routing/firewall appliance. The server is using racoon to set the VPN and is already used for another VPN that was set up years ago ...
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1answer
22 views

Topology/wiring recommended for my home network [on hold]

I come to you to see if you can advise me on the best way to connect the ISP router and openwrt router (which provides wireless access, DHCP, basic local DNS and in the future VPN) in my house ...
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0answers
12 views

How to shape bandwidth fairly between processes?

While running QBitorrent, other processes get virtually no bandwidth, as QBittorrent gobbles up all of it. Chrome loads forever, pings time out etc. I could just limit QBittorrent to not use all of ...
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0answers
33 views

Debian Stretch network boot (nfs) shutdown fails because of network service

with Debian Jessie my Raspberry Pi was working pretty well with booting from NAS. With Stretch there is an issue with shutdown (and reboot), because Stretch seems to disable the network interfaces too ...
0
votes
1answer
32 views

Reachability of custom loopback interface on different machine

I have a loopback interface on one machine with a certain IP address, and on another machine I have a static route to that loopback interface subnet. I can ping the other loopback interface when ...
1
vote
1answer
1k views

Wireless card is not detected on ubuntu and fedora

I'm currently running fedora 27 on an Acer Aspire Switch One SW1-011 (https://www.notebookcheck.info/Acer-Aspire-Switch-One-10-SW1-011-11AN.231024.0.html) according to that link it's a Realtek ...
2
votes
1answer
1k views

nmap won't recognize a hostname on my local area network

Scanning the machine on the LAN with my laptop, I got this: gabriele @ osiris { ~ } [ Tue Oct 07 ] [ 08:49 PM] nmap -sP 192.168.1.236 Starting Nmap 6.40 ( http://nmap.org ) at 2014-10-07 20:50 CEST ...
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0answers
15 views

Determining the network interface through which data is sent

I am working on a busybox embedded Linux platform which is running on a imx.6ull based development board. I have written a c++ application which enables the embedded device to collect data from ...
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2answers
36 views

Prevent netplan from creating default routes to 0.0.0.0/0

I have running an Ubuntu 18.04 with 2 ethernet NICs. On both NICs I'm using DHCP. How can I prevent netplan from creating a default route to 0.0.0.0/0 on both devices? I want one NIC routing to 0.0.0....
1
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1answer
4k views

Host-only network adapter (enp0s8) not starting on boot in CentOS7

I've installed CentOS7 in virtual box. I've 2 network cards - one host-only (vboxnet0) adapter enp0s8 (which I want to be static) and the other the NAT adapter enp0s3. The host-only adapter never ...
7
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5answers
362 views

How can I display ssh commands executed from another machine?

Can I see what other users type/execute via SSH in my server via bash or shell?
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2answers
1k views

How to display commands executed via ssh and their user's IP?

I asked a question before, but I didn't get a satisfying answer in : How can I display ssh commands executed from another machine? so I'll ask this time precisely. How to display commands and their ...
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0answers
10 views

Mac static routes with weight

We have a company VPN connection that I use on my Mac. They had it setup where only the company networks were advertised through the VPN. This meant that I was able to use my home network and the ...
5
votes
6answers
46k views

No IP address on VMware running centos 7

I just now installed Cent OS 7 on my VMware 8 and I am not able to connect it to a network. I checked the VM network and its mapped to the physical NIC. The same setting work like charm on my CentOS ...
1
vote
1answer
31 views

nat configuration for qemu-kvm guest and host networks

Under an Ubuntu 18.04 host, I have set-up an Ubuntu 10.04 guest VM from a cloned HD. The VM fires up fine, I can ssh into it from the host, but it fails to communicate outside of the host. My ...
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0answers
12 views

Using a managed VPN on a unmanaged interface with NetworkManager

Whenever I set up eno1 as a NetworkManager unmanaged interface via /etc/network/interfaces.d/eno1, I can no longer connect to my foobar vpn that is configured in NetworkManager. If I click on foobar ...
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2answers
1k views

On ssh connection the auth.log shows as source IP the external IP of the server instead of the IP of the client

I have a very odd situation with my ssh connection. Every time I connect to my server, whatever is my external ip, the connection have as source the server's external ip. Example Server S.O.: ...
5
votes
1answer
5k views

Using a bridge, an LXC container can't ping router, but the host OS can

I've got a virtual machine running under virtualbox, and in that virtual machine I've got an LXC container I'm trying to bridge to virtualbox's NAT interface: ------------- ----------- -----...
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0answers
46 views

Forwarding HTTP Request through a VPN and to a local IP [closed]

Hi, what i'm trying to do is explained as follows: I need to retrieve some JSON data from the Arduino (192.168.1.101) making an HTTP request to 80.X.X.X or to the associated DDNS. First, i have a ...
1
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1answer
2k views

GSM device unavailable in NetworkManager

I've been trying for the last few days to set up a GSM connection on my new ubuntu box. However, I can't seem to get Network Manager to manage it correctly. The box is a compulab fitlet2 and the cell ...
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0answers
30 views

SSH or VNC to my rpi not working after connecting to nordvpn

I recently got a raspberry pi and installed raspbian OS. I am trying to use this box as a headless torrent box. I am able to download torrents (with Deluge) but as soon as I connect to Nordvpn I ...