Managing and using network connectivity on a unix system

learn more… | top users | synonyms (1)

1
vote
0answers
9 views

Iptables restrict all, allow multiple specified users to destination port

This great answer tells me how to prohibit all users from connecting to remote host on specified (in this case 25) port, except one user: iptables -I OUTPUT -m owner ! --uid-owner postfix -m tcp -p ...
2
votes
0answers
12 views

Large TCP backlog in docker container, but no visible connections

In a setup with three docker instances, one running haproxy and two others running a flask-based python application through uWsgi, we run into a situation after about a day where no new connections is ...
1
vote
1answer
17 views

Poor network performance between AIX 7.1 on 1 Gbit/s and SLES 11 on 10 Gbit/s

I am having problems with the network performance between SLES and AIX. I have tested the network performance from AIX 1 Gbit/s to AIX 1 Gbit/s SLES 11 10 Gbit/s to SLES 11 10 Gbit/s AIX 1 Gbit/s to ...
2
votes
0answers
12 views

Bluetooth Tethering, no IPv4 adresse at interface bnep0

I want to tether my mobile internet from my smartphone (OnePlus One, Android) to my Laptop (Debian 8). I want achieve this without using external tools. At the arch wiki page (https://wiki.archlinux....
-1
votes
2answers
29 views

Can not set static DNS on debian

I'm using Debian jessie and I don't have network-manager or resolvconf installed and I'm using DHCP. DHCP with static DNS First of all I tried editing: /etc/network/interfaces And adding this: ...
2
votes
1answer
17 views

Linux router - Throughput speed of clients

I have a computer that is configured as a router with two NIC's, one is connected to Internet, the other is connected to the local network switch. I know that I can get the current throughput of NIC'...
1
vote
1answer
23 views

Use same IP for 2 Ethernet Adapters in different Physical networks

We have a Linux Panel with 2 Network Interfaces. On this Panel runs a software wich needs to comunicate to our devices in our network, and needs to be accessible from the customers network. One ...
0
votes
0answers
12 views

ethtool flow control icmp

I'm trying to disable ICMP directly on network cards. I have IXGBE driver 4.4.6 and ethtool 4.5 I've successfully filtered udp4 trafic with : ethtool --config-ntuple eth2 flow-type udp4 action -1 ...
0
votes
0answers
43 views

Ethernet, wireless, adapter - what are these in my OpenWRT router settings?

I am looking at my OpenWRT settings and in Network -> Interfaces -> LAN and WAN see a lot of network interfaces. And it looks to me that there are too many of them. For example, in LAN section I ...
1
vote
2answers
30 views

Lost in the world of VPN

The Q. If i have a server, is it possible to have that server with a VPN connection, while simultaneously having an entirely separate connection to be able to SSH to from client machine. The Why. I ...
-1
votes
0answers
16 views

How to run a function for a specific received packet? [duplicate]

I am doing an experiment for my master thesis. I want to run a function (e.g. multiply two numbers) when a specific packet is received (e.g. a packet with destination TCP port 6666). For example, I ...
0
votes
0answers
27 views

Can detect but not connect to 5ghz?

One night I found out that I could no longer connect to my 5Ghz network. It happened rather suddenly. My fear is that it's a problem with the card, because I also cannot connect on Windows. I can see ...
0
votes
1answer
25 views

SSH DNS lookup on local IP addresses [duplicate]

As I have come to understand, SSH always goes through the process of reverse DNS lookups whether you are connecting to user@example.com or a local server calleduser@192.168.0.56. I do not know, ...
0
votes
1answer
47 views

SSH takes too long to ask for password

I've seen many other questions on this subject but none seem to actually solve my problem. Like any other day, I connect to my LOCAL Raspberry Pi server from my client machine at 192.168.0.5 with ssh ...
1
vote
0answers
13 views

iptables routing input and forward paths

I would like to know the flow of a packet given the configuration below. Suppose that I setup an adhoc network between my android phone and a NIC on my linux box. I then setup the android phone to ...
4
votes
1answer
29 views

Why does reading /proc/net/tcp take a long time ss is quick to return the same sort of data about the connections table?

On Linux 2.6.32, if you read (for example, cat) /proc/net/tcp, on a very loaded system (for example, a web server), you will find that reading 100K entries takes over 30 seconds. That's a long time. ...
2
votes
0answers
23 views

Multicasting with a Debian Router

I have a local network and I want to use NTP in multicast mode on this LAN. The first step to do this is to get multicast networking to work first. In the network I have 5 Debian machines all ...
0
votes
0answers
51 views

Ubuntu not allowing traffic to ports 1 - 1024

I seem to have encountered a weird issue whereby my ubuntu box is not allowing incoming traffic to the first 1024 ports or so, for both TCP and UDP. My iptables policy is set to ACCEPT for all 3 ...
3
votes
0answers
24 views

SoftIRQs and Fast Packet Processing on Linux network

I have been reading about performance tuning of Linux to get the fastest packet processing times when receiving financial market data. I see that when the NIC receives a packet, it puts it in memory ...
1
vote
0answers
21 views

Shutdown problem on Lenovo G50 after installing Linux Mint 17.3

After installing successfully Linux Mint 17.3 on Lenovo G50, its not rebooted. The error is : [397.188708] Fixing recursive fault but reboot is needed! [400.538090] init: mdm main process (2363) ...
1
vote
1answer
44 views

Debian - No wired connection after restart

Last night I was working on my computer, for reference I'm using i3, and decided to uninstall XFCE4, as I felt I didn't need it. The next morning I turned on my computer and have no wired connection. ...
1
vote
0answers
14 views

/etc/network/interfaces automatically startup pppoe on wireless lan (wlan0) on boot and also make it persistent

I do have the following setting OK in /etc/network/interfaces: auto wlan0 auto dsl-provider iface wlan0 inet static address 192.168.XXX.XXX netmask 255.255.255.0 broadcast 192.168.XXX.255 wpa-ssid ...
0
votes
2answers
27 views

find IP and PORT in use by Apache

How can I find which IP:PORT Apache web server is monitoring? There are some network commands, but they show the TCP port in use. The machine has multiple network interfaces and the Listen section in ...
2
votes
2answers
43 views

Ping from subinterface

I have a sub-interface eth0:0 auto eth0:0 iface eth0:0 inet static address 192.168.2.96 netmask 255.255.255.0 gateway 192.168.2.1 and I try ping -I eth0:0 8.8.8.8 and I ...
1
vote
0answers
26 views

Bash check if firefox use internet

I want to check how much internet use Firefox with a shell script. Here I found good examples to see performances. #!/bin/sh free -m | awk 'NR==2{printf "Memory Usage: %s/%sMB (%.2f%%)\n", $3,$2,$3*...
3
votes
2answers
48 views

Assigning static IP address using nmcli

So I'm trying to give a VM a static IP address, this case has been particularly stubborn. The VM is running on a ESXi cluster with its own public IP range. I had it (sorta) working with an IPv4 ...
0
votes
1answer
25 views

bridge or route wlan traffic to eth

Have been trying to make a laptop share its wireless connection via ethernet to other devices, but am getting nowhere. First tried bridging, but soon found out bridging wireless interfaces is not that ...
0
votes
1answer
21 views

Resetting network interfaces when waking up from suspension

I carry my laptop in "suspended" state and routinely use the Ethernet port. When I move it, the usual sequence of event is: suspend, unplug all the wires (power, Ethernet), put in bag, move, take from ...
0
votes
0answers
20 views

why I can't log-in into my PS TP link WPS510U via browser [closed]

I've a TP link printer server WPS510U which is set to default factory. By NetworkManager or manual terminal configuration I've set a manual IPv4 address for an ad-hoc connection with my PS (192.168.0....
0
votes
2answers
26 views

Client route for OpenVPN Access Server

I am running OpenVPN Access Server and I'd like to push a route to every client on connection that is the equivalent of: sudo ip route add 172.17.0.0/24 via 172.27.232.1 Where should I go to set ...
1
vote
1answer
38 views

Strange MTU value from ping

I am trying to make on-line steam games work on my laptop. I have this problem: games can't connect to game servers if I run them on linux. If I run them on Windows they work fine. Other Windows ...
1
vote
0answers
35 views

Unknown network connections in nethogs (is it safe?)

It's about a month that I see some unknown connections in nethogs and I tried to understand what program is responsible for them but I failed. I'm not sure but it seems that my Internet connection ...
1
vote
0answers
30 views

Calculating the total traffic generated by an application in a network

I have network (shown above) with the same application (Appx) running on the nodes (Linux nodes). This Appx has data to send the same copy of the Appx running in each node (i.e. each Appx generates ...
2
votes
0answers
25 views

How to share a DHCP Server(Debian) that is created on VMware to other PC in the same switch

I've created a dhcp server(in Debian) on VMware. When I launch a new virtual machine on the same computer it works fine, it receives an IP address from the DHCP server. But how to connect other ...
0
votes
1answer
24 views

Bourne to grep and forward specific text from across a LAN

I'd like to develop a shell that keeps forwarding me the greped text(say compilation errors or warnings, in a single txt output) to some E-mail ID or on some NAS mount point, most importantly from ...
1
vote
2answers
40 views

How ifconfg fetch enabled NICs?

I have searched this for a while, but there was no clear keyword to find same question. Briefly showing my question: ifconfig only shows enable NICs. # ifconfig br0 Link encap:Ethernet ...
1
vote
1answer
20 views

Add parameters to NFS mount

I try to start Android on device via NFS and TFTP. Everything goes good until Android system starts booting. Something happens with network parameters and connection falls and boot freezes [ 60....
-2
votes
2answers
40 views

How to restart network in ubuntu server 14.04.04?

I tried using service network restart and /etc/init.d/networking restart, what command could I use now?
0
votes
0answers
56 views

How do I set up network connection via 3G USB modem for Linux?

I've spent a lot of time searching for a solution, but now I'm here. I need to set up LG 3G USB modem for my Ubuntu 16.04. The system is able to see the device: $ lsusb Bus 001 Device 004: ID 1004:...
0
votes
0answers
7 views

Why doesn't wpa_supplicant work when using crontab job?

I am writing a script that is installed via a crontab job. The point of the script is to locate a specific AP and connect to it on start up. The script will log its progress to a text file called, "...
1
vote
1answer
21 views

SSH in local network while hosting same network

I have the following setup: Computer A has a Wifi-USB adapter (and is a robot, so it doesn't need real internet access). It's running Ubuntu 14.04. Computer B is my Laptop running Ubuntu 14.04 also. ...
1
vote
0answers
16 views

If it possible to permanently set a loose source routing option to all ip packages to a specific ip address?

First of all, the loose source routing is a kind of ip options which requires a selected hop to route this package. I wonder if it possible to set loose source routing option on specific ip packages(...
1
vote
2answers
28 views

set up NFS two way syncronization [closed]

I have two servers that I want to "share" the home folder of, such that when I make changes on Server A they appear on Server B and when I make changes on Server B they appear on Server A. Right now ...
1
vote
1answer
56 views

How would I limit connections to certain services, to be only accesed via a connection coming from a sub-domains?

I have a personall machine running Ubuntu 14.04.4 LTS. I use it to host a Teamspeak and a Minecraft server and also a website. I am trying to make sub-domains to only point to the right services. So ...
0
votes
0answers
39 views

Arch-ARM: netctl not working correctly at boot

I've created a netctl profile that assigns a static address and alias to my eth0 NIC, however when I boot the interface doesn't come up at all. I check with systemctl status netctl@eth0.service and ...
0
votes
0answers
14 views

SAMBA Share Not ReadWrite

I've set up a folder (on srv005) /mnt/local/data owned by msc:msc_group. drwxr-xr-x 4 msc msc_group 4096 Jun 9 22:33 data I've set up SAMBA with the following share options: [srv005_data] comment ...
0
votes
0answers
24 views

My network interface disappears from /run/network/ifstate

Here's the relevant parts of my interfaces configuration file: # grep -vP '^(#|$)' /etc/network/interfaces auto lo iface lo inet loopback auto eth0 iface eth0 inet static address 192.168.0.10/24 ...
1
vote
0answers
52 views

Why is my network unreachable in virtual machine with RHEL 7.2?

I got a 30-Day evaluation of RHEL 7.2. I installed into a VirtualBox machine, and tried to register my subscription: # subscription-manager register Registering to: subscription.rhn.redhat.com:443/...
0
votes
0answers
19 views

What would cause itermittent internet connectivity on my server?

I occasionally have trouble with an ubuntu VM I set up for testing developement work - it occasionally becomes inaccessible to ssh, can't connect to archive.ubuntu.com for updates, etc. It has two ...
0
votes
0answers
14 views

Multiple Subinterfaces on a Wireless NIC (Ubuntu)

I need to create multiple subinterfaces on a wireless NIC. I have done it on a regular wired NIC before but before I test myself, I wanted to find out from the community if it is possible. The ...