I am running Ubuntu server 14.04.3. I have smcroute installed – Version 0.95, Build 130523. When I attempt to start the daemon I get the error message: ERRO: addVIF, out of VIF space;, this happens after it attempts to add the 33rd network interface of my machine. Looking in mroute.h in /usr/include/lin…
Tag: networking
Raw Sockets in C
1. The linux manual page says about this code. In socket option, if IP_HDRINCL is set, I can make IP header. Am I right? If it’s right, above socket also let me make TCP header, too? Then, if IP_HDRINCL is not set, what means above socket? 2. what means above code comparing to number 1 question’s …
RaspBerry Pi Command Line/Application – List IP Devices
I’m trying to make a very simple Raspberry Pi application that would auto-update with all the IP addresses, Mac addresses, and their respective device names that are all on the same network. I have absolutely no idea where to start, any recommendations on how to get this done? I play to connect a LCD an…
Attempting to send TCP SYN packet with data and RST with data, but raw data field disappears in transit. Why?
I’m attempting to craft a raw TCP packet to send over Ether in a raw socket on a linux client and server. The special part of the TCP packet is that I’m attempting to use the raw data field of the TCP SYN packet and RST packet to send data back and forth (for a proof of concept about an
Is libpcap implemented by socket API?
libpcap is used for package capturing. As I understand, it can capture the network packages from all ports. And it can capture the package data in link layer (such as ethernet frame). This looks a little confusing to me, because it seems impossible to intercept all network traffic (from all ports) by just usi…
How to get the URL or IP of a load balancer from DNS of a website?
nslookup is a network administration command-line tool available for many computer operating systems for querying the Domain Name System (DNS) to obtain domain name or IP address mapping or for any other specific DNS record. So, nslookup returns the endpoint(s) of a url. But if I needs to get the intermediate…
Get Subnet mask in Linux using bash
I am using bash to get the IP address of my machine with that script: And now I am trying to get the Subnet Mask in this type: But I have no idea how can I do that. Answer there are couple of ways to achieve this: first: to print the mask in format 255.255.255.0, you can use this: second:
Linux: Port Isolation on a Bridge to use OLSR correctly
On a router running OLSR there are four ports/interfaces where connected devices talk OLSR to each other. Now i dont like to use an IP address for each interface but instead bridge them all and set just one IP address on the bridge. The problem now is, those devices should NOT see each other on layer2, else o…
Simulate VPN connection in docker
I want to simulate a VPN traffic on my machine. I’ve set up VPN server which runs inside a docker image. I can successfully log in. The problem is that the docker image is running on my machine on the default docker’s bridge – docker0. There is no change if I do connect to machine using VPN …
ip route add by specifying source address in the same network
I have 4 pc´s and another pc, call it proxy, all being in the same network: 172.16.96.0/20 . I can ping between each other. But, I want to separate them into 2. That is: pc1 is directly connected to pc2 pc3 is directly connected to pc4 But, all traffic from pc1 or pc2 to pc3 or pc4 has to go