Managing and using network connectivity on a unix system

learn more… | top users | synonyms (1)

0
votes
0answers
20 views

Connected to wifi but no internet access

Unable to be pinged from other machines (other machine returns 'Request timed out') Unable to ping the router or any other device (returns 'destination Host unreachable) Unable to use the internet ...
2
votes
1answer
42 views

make my Debian laptop switch autoamtically to a backup connection

I have a laptop with Debian OS installed under it. It is initially connected to the internet using an Ethernet cable (via a modem) and I want to automatically switch to a backup wifi connection (which ...
0
votes
0answers
13 views

How to restrict access of a process to specific ports?

How can I restrict access of a process to use only specific ports, or block it if it uses non-allowed ports?
2
votes
1answer
35 views

Secure way to allow any user to run programs in specific network namespace

I have a cell modem connected to my server that I want to use as a means to get notification emails out when the landline dies. To nicely separate normal network access and this exceptional cell ...
1
vote
0answers
32 views

links are always NO-CARRIER, but expected to work

At some point I start receiving "NO-CARRIER" error message. What does it mean and how can I fix it? My links are "physically up" - green lights are blinking. On the opposite side link is up, but no ...
2
votes
0answers
37 views

Why is dhclient making DHCP requests on a static interface?

I'm setting up a new Debian system. I have a static IP configured on an interface in /etc/networks/interfaces like so: # The loopback network interface auto lo iface lo inet loopback # The primary ...
1
vote
1answer
77 views

Loading kernel modules that were compiled for another kernel failed

I want to load kernel modules, ip_gre.ko and gre.ko, on a embedded-device running embedded-linux to make that device to support GRE protocol. Since I do not want to change Embedded-linux device's ...
0
votes
0answers
61 views

Best way to transparently redirect traffic to proxy

I've implemented a wireless router using hostapd on Debian Wheezy running on a Banana-PI. To access the internet, this router is attached to another network that I haven't any control of via ethernet. ...
0
votes
0answers
17 views

Send raw IP packets to a server, forward them to their destination addresses, and give responses back to clients

A similar question was asked here. But I'm not sure I need OpenVPN for what I'm going to do. I have an Android device with a TUN network interface and capture IP packets. Then I'd like to forward ...
0
votes
1answer
45 views

Redirect traffic through the server

My task is to redirect traffic (port range) through the server. Here is the schema: Why NAT is not appropriate here: If NAT is set to "Tunnel Server", then all users will be assigned the same IP. ...
0
votes
2answers
30 views

Get Any Interface's Router Address

How can I know what the router's address is when I am on multiple interface? I know by using netstat -rn I can have the dominating interface's gateway, which is the router's address. But what about ...
1
vote
0answers
29 views

Appearing to be on the same network

I have a user that needs to connect to a machine located on a private network at another facility. Basically 192.168.0.20 -> 192.168.0.1 -> Internet -> 192.168.1.1 -> 192.168.2.1 -> ...
2
votes
1answer
79 views

netctl not auto-connecting consistently

I am trying to setup my wifi network in Arch Linux ARM to auto-connect at home and office. But it is not always connecting automatically as intended. netctl list * wlan0-Spaceship wlan0-Cremehead ...
2
votes
2answers
40 views

iproute2 command to enable a IPv4 address

I am investigating how to have iproute2 commands replace the old ifconfig and ifup ifdown command, and I found out something interesting. My NIC setup is: [16:07:41 root@vm network-scripts ]# cat ...
0
votes
1answer
25 views

Nat with saving real client IP

I have this schema: Client -> NAT server -> Game server On NAT server I have the following rules: iptables -A FORWARD -d $MC_IP -p tcp --dport 25550:25580 -j ACCEPT iptables -t nat -A PREROUTING -d ...
1
vote
0answers
40 views

Setup public IP address on LXC container

Can anyone tell me how to setup a network interface for each LXC container so that each container can have its own dedicated IP address? Here's what the /etc/network/interfaces file on my host node ...
1
vote
2answers
33 views

how to find URLs accessed by a process

Is there a way to monitor and get a listing of URLs accessed over HTTP by a process running in my local machine? Failing that, what would be closer to the above information? My use case is that I have ...
0
votes
1answer
44 views

libvirt - virbr0 - setting the IP address

I am having issues with setting the IP address of the virbr0 interface created by libvirtd. I have configured a different IP in the xml file that configures networking (or so I thought), but it still ...
-1
votes
1answer
51 views

How to change hostname on Linux and make it appear on a network? [duplicate]

First, what is the correct way to change the hostname in Linux ? I followed some steps on the internet and sometimes it does not take effect. Besides, the new hostname does not appear when I ping my ...
-2
votes
2answers
70 views

How can I find the name of my Network Interface [closed]

I have a project that requires me to scan the local network. I found a program on the internet that allows the local network scanner condition, but I brought the gold @ IP argument in my network ...
3
votes
5answers
129 views

Get devices name on the network

As in the title i wanted to know all the devices name on the network. I've already tried without great success many commands found on the web, but nothing worked like i wanted to. Basically, when i ...
1
vote
1answer
26 views

How to find process which flood the whole network

I have a laptop with Fedora 21 and TP-Link router with DD-WRT software. Sometimes my whole internet stops for any device. When I reboot my laptop or just I turn off wireless, the internet works fine. ...
0
votes
0answers
59 views

Get real IP after OpenVPN tunneling

I try to route traffic from one Server to another using OpenVPN. In the end users should only connect to the forwarding machine. It basically works using this iptables rules: iptables -t nat -A ...
0
votes
1answer
36 views

Debian wired connection static IP wont connect

I've installed Debian with xfce and did some configuring by installing themes, configuring xfce, installing and uninstalling software; the usual. Anyway, after a reboot I can't connect to the ...
0
votes
1answer
38 views

tcpdump -i any and promiscuous mode

From the man page for tcpdump 4.1.1 (yes I know its old) -i Listen on interface. If unspecified, tcpdump searches the system interface list for the lowest numbered, configured ...
2
votes
0answers
40 views

How to monitor UPnP communication?

My Computer is connected to router that supports UPnP, however it's not the last router on the way to the WAN. So, mapping there has no effect. I've got VPS and I've made a VPN network (computer ...
0
votes
2answers
141 views

Debian autossh boot script not working properly

I wrote the start script at the bottom of this question to try to get one of my devices to automatically create several remote forwarded ports with my VPS upon boot. (I've stripped the LSB tags to ...
0
votes
0answers
11 views

Learning about interface between Network and Running Daemons (PHP,MySQL) - for scaling

I am a PHP/MySQL/jQuery programmer and coder, not a hardware guy. My new job involves scaling a LAMP server. This is a question of "what are the terms I should even be searching for" as I need to ...
1
vote
0answers
12 views

network.service - after executing “telinit” network interfaces doesn't start

When I start RHEL 7 everything is fine, my network functions, I can ping other PC's etc: [root@localhost]# service network status Configured devices: lo eno1 enp2s0f0Team enp2s0f1Team team0 team0.300 ...
2
votes
2answers
60 views

How do daemons like apache or bind open ports below 1024?

I know that ports below 1024 are protected and can't be opened by a user without sufficient permission. However, I'm wondering how daemons such as bind or apache can do so, though they aren't running ...
1
vote
3answers
51 views

What is the preferred way of using low port numbers in linux?

Long story short: I want Glassfish to listen to port 80 so that you don't have to specify port when typing in the url, but linux doesn't permit using low port numbers without root and running ...
1
vote
0answers
153 views

isc-dhcp-relay service doesn't work

192.168.2.1(dhcp server) -> (eth1 192.168.2.3)[ubuntu 14.04 dhcp relay server](eth0 192.168.1.1) -> Client isc-dhcp-relay successful installed, configuration file is #/etc/default/isc-dhcp-relay ...
1
vote
0answers
38 views

Specifically what advantages does Kali Linux have other than preinstalled packages? [closed]

I have been using Kali Linux increasingly over the last few months. I also have an Ubuntu system, and have found that there are many similar tutorials on how to install Kali tools on Ubuntu. However, ...
3
votes
1answer
120 views

Routing ALL traffic through VPS

I recently acquired a Raspberry Pi and I'm setting it up for various things. I have a local router that the Pi is wired into along with my desktop computer. I want to be able to access the Pi from ...
1
vote
0answers
172 views

VirtualBox Bridged Networking is not working (NAT and Host-Only works)

I'll try to be brief and include all the things I've tried out so far: Guest OS: Debian Wheezy Host OS: Windows 7 Setting networking to NAT works. Setting networking to host-only works as well. ...
2
votes
1answer
27 views

How to change configuration of eth0 without restarting other interface (CentOS, Redhat)

I need to setup a static IP for eth0, my server has multiple network interfaces and I don't want to bring any of them, except for eth0 down. I found lot of guides like ...
1
vote
0answers
73 views

monitor mode capturing wifi

I have a network, which has 2 nodes (a phone, a MacBook) both are connected to same wireless network, I know the SSID and password for the wireless network password: mypassword ssid: myssid security: ...
1
vote
1answer
33 views

How does Linux prevent applications from sending more packets than the link can handle without dropping packets?

I couldn't make the question any clearer so here's an example scenario: Given a Linux machine connected to an IP network through a physical interface of bandwidth 10Mbps (or a higher speed interface ...
0
votes
0answers
39 views

Why must a server know its own host-name and domain-name?

In Linux, a server can set its own host-name and domain-name through sethostname() and setdomainname(). I just wonder, however, why must a server know its own host-name and domain-name? To my ...
1
vote
0answers
40 views

Network tool to monitor IP packet fragmentation

Is there a tool, similar to iptraf, that would let me see how many incoming/outgoing IP packets get fragmented/defragmented, and what percent of traffic they are? I know this can be counted with the ...
1
vote
0answers
64 views

Unable To Bridge Two Teamed Interfaces - Advice?

Before the wall of code I'll explain the situation. I'm trying to set up two interfaces to be teamed together, and from that team create a bridge. I've been studying for the RHCE and I believe this ...
1
vote
0answers
56 views

IP packets fragment randomly

I've observed the strangest thing - the same packet, same size, send through the same interface sometimes gets send whole, and sometimes gets fragmented, as if it exceeded the interface MTU... 1472 ...
1
vote
1answer
146 views

forward packets from one interface to another interface using iptables

I have an embeded system with 2 interfaces e0 and m0, whose ips are 10.0.0.20 and 192.168.0.20, respectively. Incoming packets into e0 have an ip of 10.0.0.10 and should be forwarded to m0 interface ...
1
vote
1answer
10 views

Virtual eth-adapter in networking-configuration

I have on my Debian en eth0-interface and I need the interface to listen to other IP's. I know I can create it with the following command ifconfig eth0:1 10.10.10.20/24 With this command everything ...
1
vote
1answer
57 views

Is Super server (inted / xinetd/… ) comes with Ubuntu default?

Few days back I learn about super server in networking. Then I looked for /etc/inetd.conf and /etc/xinetd.d and found neither of them in Ubuntu. Note: I know only these two types of super server ...
0
votes
1answer
24 views

Historical bandwidth data in a console? (save/load statistics)

So, I found that nload and iftop displays the amount of data that passed and how fast. Now, is there anything like those that can save/load statistics? I want to measure the amount of data I download ...
0
votes
1answer
79 views

SIPp “hello world” message to Asterisk

How do I run diagnostics against Asterisk? Asterisk is running on tleilax; and doge is on the same network (My network topology isn't optimal). Specifically, I want to do something like: sipp ...
2
votes
1answer
38 views

asterisk network topology — KISS

is this the typical Asterisk topology??? On my home system, I have the Asterisk server, tleilax, and the client, doge, connecting into my router -- so that they're both on the same network. The IP ...
0
votes
1answer
63 views

yast routing problem — connect: Network is unreachable

---------------------------------------------------update----------------------- on doge the route works: thufir@doge:~$ thufir@doge:~$ route Kernel IP routing table Destination Gateway ...
1
vote
0answers
35 views

converting teaming to bonding

RHEL 7 contains bond2team tool but it doesn't contains opposite team2bond tool. I need to convert my teaming files to bonding (please don't ask why, this is for testing purposes). This is my teaming ...