Managing and using network connectivity on a unix system

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2
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1answer
269 views

Interface Priority in the Face of VPN

I have a few interfaces: wlan0, eth0, lo, and sometimes tun0. When I connect to the Juniper VPN, creating a tun0 interface, my existing connections on other interfaces (perhaps with the exception of ...
3
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1answer
1k views

Monitor outgoing web requests as they’re happening

I want to see a list of all outgoing HTTP requests from my desktop. I think it should be possible to monitor HTTPS hostnames as well for local clients using Server Name Indication (SNI). OS X has a ...
2
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0answers
94 views

Last data traffic time for a TCP socket

Is it possible, to find out when was the last time there was any traffic on an opened TCP socket? Keepalive and timeout timers are based on this statistic, so I guess it has to be stored somewhere. ...
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5answers
884 views

How to measure network traffic usage?

I want to know how much bandwidth my server is using. How much in, how much out. How do I know that? I think there is a software, netstat or something that took care that sort of thing.
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2answers
632 views

How to find transmission speed?

Two host machine's one as a client and other as a server, i am testing udp load-test in these two machines.Machine Ethernet speed is 100 Mbps but i want to send 30000 packets each of 512 bytes at 1 ...
12
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4answers
759 views

Why does *BSD uses driver specific names for network interfaces? Does it imply limitations?

I notice that depending on the brand of the network card, interface names differ (driver dependent I suppose). Why does *BSD uses driver specific names for network interfaces? Does it mean there is ...
4
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1answer
203 views

Create map network_iface_name <--> IPv4 address

I'd like to implement a bash script that creates a mapping between the network cards (or interfaces) names in my computer and their IP address (in CIDR format, if possible). The goal is having ...
9
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1answer
1k views

Send a packet over the network even when its target is the local host

Under Linux if you send a packet to the address of one of its network interfaces, this packet is routed internally, it is never sent over the network. That's the right thing in 99.99% of the cases. ...
1
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1answer
194 views

Connecting to Verizon Mifi (wirelss hotspot) breaks everything

This question is obviously network related, but I thought it would be more appropriately placed in this forum because it's really not so much a connectivity issue. I recently got my hands on one of ...
3
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1answer
224 views

How to tell if two ethernet interfaces are on the same lan?

I have to secure interfaces on Linux servers by setting bonding interfaces. The cabling information is not accurate. Is there a simple way to know if two interfaces are connected to the same LAN? ...
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0answers
313 views

How to make linux see my internet connection?

I'm sort of booting off of a Mint 17 LiveCD (the situation is described here: How can i make my pc boot back into windows?) and the network does not work. It's wired if it matter. I've also tried to ...
4
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3answers
5k views

MySQL Workbench Cannot start SSH tunnel manager

I don't know why this error is happening when I try to connect by MySQL Workbench. Cannot start SSH tunnel manager. I'm using slackware 14.1 and installed all dependencies.    
1
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1answer
366 views

masscan. how to configure Linux?

I've set this in my sysctl.conf: net.netfilter.nf_conntrack_max=268435456 Because, this border 16,777,216 achieved very quick. Also, I've decrease timeouts: net.ipv4.tcp_fin_timeout = 30 net....
5
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1answer
68 views

Testing whether a file is local

I need to test in a script, whether a file is from a network mount or truly local. To be more clear: I need to test, whether parsing the contents will be fast or slow, but for my case local vs network ...
1
vote
1answer
191 views

DDNS (dynamic-dns) setup and adding a hostname to a device (to be visible on the network)

How do I provide a fixed Hostname to my device so that a netscan can shows up the device name across all platforms? How can I reach the device using the hostname/MAC-ID (something which is fixed) ...
2
votes
1answer
2k views

set ip default outgoing in centos

I have server which has Centos and I want to change the outgoing IP address. This is the output of my route and route list commands. [root@marketport tmp]# route -n Kernel IP routing table ...
5
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2answers
6k views

Use an USB tethered phone as network adapter

I am running CentOS 6 and was able to tether my HTC phone using a proxy called proxoid . This allows me to redirect HTTP. But how do I redirect the entire TCP traffic, e.g. if I need to setup openvpn ...
3
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3answers
514 views

What happens to local LAN traffic on linux to non-loopback addresses?

One thing I've never quite understood on Linux is what happens to local traffic that isn't directed at loopback. For example, given the following network setup: [root@pe-323-master ~]# ifconfig eth0 ...
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0answers
1k views

Guest VMs unable to ping each other within a custom host-only network in vmware workstation

I have created a custom host only network VMNet2 (without dhcp) in VMware workstation and connected my three VMs with this network. But the problem is: I cannot ping any VM from any other VM. However ...
4
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1answer
14k views

SSH: Network is unreachable (caused by router)

I've searched solution in Google for 3 days, when I decided to write here. I have a router, so in my house is WLAN. I use laptop when I stay at home. In another city in my office I have a second ...
2
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2answers
5k views

How do I set the preferred wireless network in Linux Mint 17?

I'm currently in an environment with two wireless networks: OrganizationFoo, which is present pretty much everywhere I go, and OrganizationFooSubset, which is only present in a certain location. When ...
2
votes
1answer
2k views

Capture web traffic grouped by individual TCP streams

As far as I know a HTTP request and response constructs one TCP connection. To debug a web application on a GUI-less server, I'd like to be able to capture these TCP streams in a single ...
7
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1answer
426 views

Installing USR 5422 on Ubuntu 12.04

I am a newbie to Linux. I was trying to set up the USR5422 USB adapter. It worked fine for the first time, but since then it freezes the computer most of the time. What commands can I fire to see ...
2
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3answers
895 views

Unable to access CentOS setup Network Configuration after attempting Python update

I attempted to update Python on my CentOS 5.6 VM and have encountered some issues afterward. Initially, yum wouldn't work, but I have resolved that. However, now I am unable to access the Network ...
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0answers
419 views

Packets sent through TUN interface not routed

I have a C program attached to a TUN interface. In my C program, I'm building packets and writing them to the TUN interface. Now to check if packets are really sent from my TUN interface I use ...
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2answers
64 views

Start the networking from scratch

Let us assume I have a computer that for some reasons has had all the networking information, in particular the stuff in /etc, wiped. Furthermore whatever caused the information to be wiped prevents ...
2
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1answer
2k views

Broadcom Corporation BCM4313 WLAN does not work on installed Arch

I have a Broadcom Corporation BCM4313 WLAN Controller in my netbook. When I boot the Arch live ISO and set up the network with wpa_supplicant everything works fine. On the installed Arch I get the ...
2
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2answers
6k views

eth0 not installed on CentOS

How would I go about installing eth0 on CentOS? When I do ifconfig -a, eth0 is not there. Here is the output of ip link: 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue link/loopback ...
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0answers
287 views

Tools to inspect local network, and find local IP address of device?

This is my specific context (Latex/TikZ code for the diagram below): Now this local "Router", has broke down several times, and several different devices have had its role (sometimes they have a ...
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2answers
2k views

How to use netstat command

My question is what does it mean to LISTEN or ACCEPT on a port as it relates to my example? Example: I have a tomcat server, and It will use port 8080. I want to make sure that port is available for ...
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0answers
228 views

How do I control ip routing in the new firewalld?

I have the following scenario: Our fedora server is connected to the internet on eth0 and has a second nic, wlan0 acting as an access point. The purpose of the access point is to provide a connection ...
1
vote
1answer
133 views

What is the foolproof/proper way to set hostname and domain on CentOS

I've seen a few ways of changing hostnames of domain names. One way is to issue the hostname command followed by the name such as: hostname localhost.localdomain /etc/sysconfig/network also has a ...
0
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3answers
664 views

Fedora 18 host cannot ping Windows XP guest

I have my laptop running Fedora 18. I want to run a Windows XP guest using VirtualBox 4.2.6. My configuration seems correct, here is my networking report. Fedora 18 host lo: flags=73<UP,LOOPBACK,...
2
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2answers
213 views

Force IPv6 only through Miredo

I have an Ubuntu PC with Miredo's implementation of the Teredo protocol. I want to temporarily make it so that I can access IPv6-only addresses with all IPv4 networking available solely for Miredo to ...
3
votes
3answers
165 views

linux interface to get connected IPs

Is there an interface to get the currently connected IPs and their state in Linux? I am aware of ss and netstat, but I want to use /proc/ or some other "official" kernel interface that already has ...
1
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1answer
534 views

Configure NAT filtring behavior with iptables

I'm using this rule to configure SNAT: iptables -t nat -A POSTROUTING -o eth1 -j SNAT --to-source 193.49.142.107:4000 I want to specify a rule to filter out packets not destined to the internal ...
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0answers
69 views

How can I make CentOS 6 treating WiFi flexibly like Ubuntu 12.04?

In my office, I have AT&T Uverse. The router is a 2wire 3600HGV. The WiFI is provided by a Cisco Linksys E1000 that is plugged in the 2wire device. With my notebook running Ubuntu 12.04 LTS ...
1
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2answers
394 views

what is 'smakynet' in the netstat result?

after logging into a server, I used netstat to check out the ports of this server and wanted to find which port was communicating with me My IP is 143.248.143.198 and my search results are like ...
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0answers
39 views

Why do I get “authentication” errors on this “Open” configuration?

I have the following ifcfg-wlan0 file: DEVICE=wlan0 BOOTPROTO=none ONBOOT=yes IPADDR=192.168.5.1 NETMASK=255.255.255.0 NETWORK=192.168.5.0 NAME=wlan0 USERCTL=no the following dhcpd.conf file: ...
2
votes
1answer
926 views

Why is the 'foreign address' not IP address but something like this?

I never learned network programming and this kind of stuff properly. Only know very basic stuff like IP address and just a vague concept of what ports and TCP/IP are. Here, I connected to my lab's ...
1
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1answer
289 views

Monitor internet for dropouts

I've been having issues with my wifi with frequent drop outs. So I've decided to check if the drop outs are wifi related or internet related by connecting my laptop via ethernet and monitoring it for ...
4
votes
2answers
5k views

sending email to IP address via postfix

My friend and I have configured two Postfix mail servers on our laptops. We succeeded in sending mail to a real network (to some Gmail accounts) from our computers; that was the easy part. We now ...
7
votes
1answer
285 views

FreeBSD systat doesn't calculate upload speed/total on wlan0

When I call systat -if shows that wlan0 out traffic/peak/total are 0 kb(/s). I'm using wlan0 for networking, internet down/upload are working. The in traffic/peak/total are OK. The wifi chip is ...
1
vote
1answer
193 views

LVS is not accessible from the outside

I'm currently busy setting up a LVS - Linux Virtual Server: root@debian1:~# ipvsadm -L IP Virtual Server version 1.2.1 (size=4096) Prot LocalAddress:Port Scheduler Flags -> RemoteAddress:Port ...
1
vote
1answer
1k views

ssh ubuntu to android : No route to host

I am trying to log into my android phone (running sshdroid), using my laptop (ubuntu 12.04). I am on a university sub-network (on wifi), and so is my phone. I tried the following command: ssh root@...
3
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0answers
27 views

Linux network stops when transferring files [duplicate]

Running Debian, when transferring files from the server to my pc, the transfer is suddenly interrupted. Some smaller files (couple of MB) seem to work most of the time, but bigger files mostly fail at ...
2
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0answers
349 views

Broadcom or Modem wireless connection problem

I have a BMC42142 wireless adaptor lspci -vnn | grep 14e4: 02:00.0 Network controller [0280]: Broadcom Corporation BCM43142 802.11b/g/n [14e4:4365] (rev 01) and I can't connect to the wireless lan....
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0answers
182 views

Local Client/Server communication using TUN interfaces

I want to establish a local communication between a client and a server using TUN interfaces. The client program will be attached to interface TUN1 and we suppose that it has IP address @IP1. The ...
2
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0answers
643 views

Network connectivity issue between different hosts from a network namespace in one host

I have created two Ubuntu 12.04 VMs using VMWare Player with NAT network configuration. I am able to ping them from each other. After that, I created a network namespace in one of them and add a ...
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0answers
70 views

Is arp periodically called to check connectivity?

Do most of linux implementations periodically make arp requests to check connectivity? I am trying to migrate an ubuntu virtual machine and, after migration, it just loses network connectivity.