Managing and using network connectivity on a unix system

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3
votes
2answers
147 views

How can I print out information about a Wireless Access Point in range?

How can I print out information about a Wireless Access Point in range? Can I for example get the MAC address?
6
votes
1answer
3k views

LXC container network/routing issues

I have been experimenting with LXC virtualisation in order to run virtual machines on a dedicated server, but am having trouble setting up the networking properly. I am using veth bridged networking, ...
2
votes
1answer
635 views

Is it possible to use Internet Connection Sharing with DHCP?

I know it is possible to share an internet connection with another pc using ip-forwarding and masquerade. Is it possible to set up the sharing computer as a DHCP server, so the settings (ip, gateway, ...
10
votes
1answer
7k views

Buffer size for capturing packets in kernel space?

Going through the man page of tcpdump, it seems kernel can drop the packets if the buffer is full. I was wondering if: that size is configurable and/or where can I see the size for my distro? From ...
3
votes
2answers
823 views

Which user group can use the 'tap' net device?

I use the 'tap' net device with KVM to get my vm connect to the Internet. But I have to be root, or use 'sudo', which is inconvenient. I think I can put my user account into some group so I can access ...
3
votes
1answer
1k views

Is it possible to capture all network traffic using tcpdump?

I have 3 computers on the same sub-net. Computer A and B are communicating with each other (ping, telnet, etc.). I'd like to see the packets between A and B on computer C. Is it possible to do this ...
1
vote
1answer
406 views

netcat throughput low but iperf high [closed]

I was testing the throughput between two pcs connected on the same router: one with 100mbps lan, the other with 54mbps wifi. I tested both netcat and iperf and the throughtput I get is only 2.6mb/s. ...
3
votes
1answer
1k views

Mounting a network drive automatically when needed and unmount it again after some time with inactivity

I have a somewhat old NAS hosting my music collection. It is not capable of running a DAAP media server so I have mounted the music folder on my Sheevaplug (a tiny headless server running Debian) ...
0
votes
1answer
1k views

How to configure DUAL-WAN on a Linux/*BSD machine?

I have two internet connections. The cables from the two ISP's (dhcp; 1-10/10 Mbit; 2-20/20Mbit connection) are on two interfaces: eth0 and eth1. On eth3 there is a Gbit switch and on the switch there ...
0
votes
1answer
436 views

Netdiscover packages for Fedora?

Ubuntu has a program called netdiscover. Netdiscover is an active/passive address reconnaissance tool, mainly developed for those wireless networks without dhcp server, when you are wardriving. It ...
7
votes
3answers
24k views

CentOS on HyperV - eth0 not in ifconfig?

I've launched a CentOS install in HyperV and assigned a NIC the same way I've done on an Ubuntu VM, however, the device simply isn't picked up. Only my loopback is found by ifconfig. How should I go ...
1
vote
1answer
318 views

Multicast on local box

I have an application I need to interface with that listens to a multicast address. I'd like to be able to run a program I've written and have it interface with the other application by multicast ...
1
vote
2answers
2k views

Check the Existence of a Network Interface Card Redhat

I'm aware that I can use ethtool eth0|eth1|eth2 to check the existence of a NIC. But I wonder where the files are on the machine that contain information of an existing interface, as I need to use ...
5
votes
1answer
3k views

Changing Redhat Network Settings From DHCP to STATIC IP Via Configuration Files

In order to make the statically assigned IP work, I have already modified the file /etc/sysconfig/network-scripts/ifcfg-eth0 as follows: DEVICE=eth0 IPADDR=10.33.17.143 NETMASK=255.255.255.0 ...
2
votes
4answers
907 views

Is there a way to determine machine hostname without touching “/etc/hosts”?

Considering that I'm in a LAN that assigns IP addresses using DHCP (and that I'm not its administrator), how do I set things up such that when I ping <hostname> (instead of ping <IP ...
29
votes
3answers
50k views

How to make a machine accessible from the LAN using its hostname

Here are details of the machine I want to access using its hostname: $ hostname hostname $ cat /etc/hosts 127.0.0.1 localhost 127.0.1.1 hostname.company.local hostname It's a default Debian 6 ...
2
votes
2answers
1k views

iscsi target to a folder of a mounted parition?

i'm thinking about installing and setting up iscsitarget on my Debian squeeze box. so far, the examples i saw on various Google searches and the debian wiki: ...
7
votes
1answer
4k views

Why is VirtualBox Bridged networking slow

When logged into the guest, data transfer (scp) from the host is very slow (<1MB/s). Is this expected? setup: VirtualBox host is Debian Unstable VirtualBox guest is Debian 6 (Squeeze) Bridged ...
1
vote
1answer
641 views

Only allow ssh/vpn on OpenWRT

If I don't want to use wireless encryption, but I still want security and I want to use sshuttle (on the clients, see: https://github.com/apenwarr/sshuttle/) for tunneling everything through an SSH ...
5
votes
4answers
2k views

How to share the internet connection?

An ordinally network topology in picture: In words: - "server" (e.g.: an Ubuntu 10.04 LTS) is connected to the "internet" through pppoe connection - "server" is using it's wireless card in AP ...
1
vote
1answer
2k views

Redhat Network Service Restart

I modified the /etc/sysconfig/network-scripts/ifcfg-eth0 file to set a static ip for my redhat. Then I tried to use command "service network restart" to make the change stick, however, it became stuck ...
5
votes
4answers
3k views

ssh hanging then time out

I am new to ssh on linux. I have two computers connected on a switch. The first one is 192.168.1.2 and the second is 192.168.1.3. When I use the ping command I got a reply and everything is good, but ...
23
votes
1answer
11k views

Why are the first 1024 ports restricted to the root user only?

This is more idle curiosity than anything else. A friend of mine asked me 'which port range is it that only root can use under Linux?' I told him 0-1024 were restricted. Then he asked my why it was so ...
10
votes
2answers
9k views

How to refuse routes that are PUSHed by OpenVPN server?

When I establish an OpenVPN client connection over the Internet to our corporate OpenVPN server, it pushes several static routes. Unfortunately, these routes break some connectivity within my local ...
4
votes
1answer
1k views

How to set a static IP in Ubuntu

How do I set my computer to have a static IP in Ubuntu 11.04? The only two lines in /etc/network/interfaces are: auto lo iface lo inet loopback I think usually when people do this they have a wired ...
4
votes
2answers
8k views

Firmware for wireless card on Ubuntu/Debian?

This is a follow up to my previous question about Debian support for Linksys Wusb600n. I have tried running the Ubunut/Xubuntu LiveCDs and the WiFi does not come up. The Gnome Network Manager menu ...
17
votes
2answers
3k views

What is a socket?

Could someone explain to me what a socket is? I see it in many acronyms in context of SSL, etc. Also, why is it called a socket? Is it purely because it was what a name they invented? Or was it the ...
0
votes
2answers
822 views

Linksys wusb600n support on Debian-6

I'm on my way from Windows 7 to Debian 6. The only problem... I'm not sure about my network adapter. Its Linksys wusb600n and without it - no internet access for me. Does Debian 6 support it? Will ...
9
votes
2answers
1k views

How do I hide/anonymise/defend a computer when on hostile networks?

I connect to a lot of open networks when I'm pootling around. I'm fairly careful to VPN home for anything important but that's not really my boggle. The laptop runs several services (nfs, dev http ...
2
votes
1answer
1k views

Bonding wireless and 3g on Fedora 15

I have access to the internet through either wireless or a 3G CDMA card. Is it possible to bond both connections and join the bandiwdth and have a failover?
4
votes
1answer
1k views

Two IP addresses assigned to the same machine?

I seem to be using two IP addresses on my PC. I use DHCP to get an IP address and then I statically set an IP address and activate it. ifconfig says that I am using the address given by DHCP but I am ...
-2
votes
1answer
257 views

How Can I “CAM attack” a switch/router?

Does someone has any script that can "CAM attack" a switch/router, so that it will act as a HUB? Are there any tools for it in the repositories?
2
votes
5answers
753 views

Remotely access Linux box with no IP address

I have two *nix boxes that are connected via ethernet. However I only have physical access to one of them. In working on the "remote" computer I messed up the ifcfg-eth0 file and instead of typing ...
3
votes
2answers
2k views

Setup WLAN interface on Debian

I am trying to configure wlan on my dockstar. I installed wireless-tools, zd1211-firmware and wpasupplicant. My /etc/network/interfaces file looks like this: auto lo eth0 iface lo inet loopback ...
1
vote
1answer
856 views

How to access shared locations on a windows machine from a linux machine via terminal?

I’ve setup a Virtual CentOS machine and set up a bridged network and static IP so that it can communicate with other Windows machines in the network. Currently, to access any shared directory, I ...
2
votes
1answer
921 views

Tool to monitor in and out data network traffic w graphs and detailed stats

Is there a tool, that can gather stats on network usage? Requirements: Generate HTML (or other format, convertible to HTML) Time line graphs for bandwidth usage, also which hosts use the most ...
1
vote
1answer
612 views

Network fail on FreeBSD: Ping to router fails, but router believes computer is connected

I have a TP-Link TL-WN851N wireless adapter, which is based on an Atheros device. When I attempt to connect to my WPA2 wireless network, ifconfig wlan0 tells me that the connection is 'associated'. My ...
4
votes
2answers
1k views

Telnet over Ethernet for Linux?

I have used MikroTik RouterOS and I found a telnet-over-Ethernet (a layer 2 telnet), MAC telnet on it. I think it's a great tool, when SSH dies, or someone misconfigures IP Addresses. So the thing ...
4
votes
1answer
1k views

How can I configure fair bandwidth sharing between cgroups?

It's fairly easy to use tc with Stochastic Fairness Queueing (SFQ) to configure fair bandwidth sharing between flows, but an application can open multiple flows and get an unfair share of bandwidth. ...
2
votes
1answer
353 views

Сan I configure FreeBSD to use DHCP or a static IP depending on the detected ssid?

I have a FreeBSD 8 machine which can use several wireless access points. I want it to use the first available network and automatically use DHCP or a static address as required (this should be ...
0
votes
2answers
897 views

Understanding tcpdump output on a linux router

My router has an atm0 interface and a VLAN (atm0.1) interface, atm0.1 has the WAN IP address. When using tcpdump -i atm0, the packets captured are only outgoing packet (LAN to WAN). 05:34:19.504895 ...
1
vote
3answers
15k views

Installed TigerVNC, can't connect?

I've just installed TigerVNC on my Fedora 15 machine from the package manager then in terminal (as root): chkconfig vncserver on service vncserver start None gave me errors, so I went back to the ...
2
votes
1answer
2k views

Unable to make outbound SNMP connections when IPTables is enabled

I have a bunch of windows servers configured with the windows SNMP agent. Each server has four IP addresses and SNMP listens on all of them. There is something very odd with my monitoring server ...
3
votes
1answer
267 views

Set up network to share a printer connected to one particular machine on the network

How do I set up my Ubuntu machine to allow other computers to print to it? The set up is: All computers are connected to the network 1 dual Ubuntu/Windows 7 netbook 1 multibooting ...
2
votes
1answer
591 views

How to execute udhcpc as non-root

On a Linux machine, I am trying to run the udhcpc command as non-root. I am getting the error udhcpc: socket: Operation not permitted. Is there any way to execute udhcpc as a simple user in Linux?
6
votes
2answers
813 views

Configuring a vncserver so it's only accessible from my ssh tunnel

Since I use vnc through an ssh tunnel, is there any way I can block the open vnc port that the remote machine is listening on without it affecting my ability to use the ssh tunnel? Both machines are ...
2
votes
2answers
1k views

Reducing packet loss in tc rate limiting

I use this tc command to limit upload speed on an interface: tc qdisc add dev eth1 root tbf rate 2mbit burst 10kb latency 70ms peakrate 2.4mbit minburst 1540 But it results in heavy packet loss. ...
7
votes
2answers
1k views

Suggestions needed for udev, udisks, autofs, notification setup for a complete automounting solution on Linux

Continuing on Automounting plugged devices in linux, which left things a bit basic. Running Gentoo, I'm automounting a combination of local and network devices on my laptop with autofs-5.0.4-r5. Doing ...
2
votes
1answer
399 views

Can't access HTTP contents, but HTTPS and SSH are fine

I'm having a weired issue wih my Fedora 14 recently. Many details involed. Let's start from this: I've been using Fedora 14 for months, and recent few days, offten I can't access Internet for hours. ...
1
vote
3answers
703 views

How to set Internet Protocol properties using terminal?

When I set up a Virtual Machine with windows (using VMPlayer), I set the Network Connection properties from the VM settings from NAT to bridged. Then I proceed to set the following IP Properties in ...