Category Archives: computer networks

geoiplookup – look up country using IP Address or hostname

commandline session $nslookup beautifulwork.org Server: 192.168.0.1 Address: 192.168.0.1#53 Non-authoritative answer: Name: beautifulwork.org Address: 80.79.116.205 $geoiplookup 80.79.116.205 GeoIP Country Edition: EE, Estonia $nslookup www.trueangle.org Server: 192.168.0.1 Address: 192.168.0.1#53 Non-authoritative answer: www.trueangle.org canonical name = trueangle.org. Name: trueangle.org Address: 80.79.116.205 $nslookup www.gnu.org Server: 192.168.0.1 Address: 192.168.0.1#53 Non-authoritative answer: www.gnu.org canonical name = wildebeest.gnu.org. Name: wildebeest.gnu.org Address: 208.118.235.148 …

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tshark – Dump and analyze network traffic

ABOUT tshark TShark is a command-line network traffic analyzer that enables you to capture packet data from a live network or read packets from a previously saved capture file by either printing a decoded form of those packets to the standard output or by writing the packets to a file. Without any options, TShark works …

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nmap – Network exploration tool and security / port scanner

commandline session $nmap –reason 127.0.0.1 Starting Nmap 6.00 ( http://nmap.org ) at 2013-09-06 21:58 IST Nmap scan report for localhost.localdomain (127.0.0.1) Host is up, received conn-refused (0.0013s latency). Not shown: 995 closed ports Reason: 995 conn-refused PORT STATE SERVICE REASON 22/tcp open ssh syn-ack 25/tcp open smtp syn-ack 111/tcp open rpcbind syn-ack 389/tcp open ldap …

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what is tcp_retrans_collapse – BOOLEAN ?

ABOUT tcp_retrans_collapse This variable implements a bug in the TCP protocol so it will be able to talk to certain other buggy TCP stacks. Without implementing this bug in the TCP stack, we would be unable to talk to certain printers that has this bug built in. This bug makes the TCP stack try to …

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How to make tcpdump output without address to name conversion ?

ABOUT tcpdump tcpdump is a common packet analyzer that runs under the command line. It allows the user to display TCP/IP and other packets being transmitted or received over a network to which the computer is attached.[3] Distributed under the BSD license,[4] tcpdump is free software. Tcpdump works on most Unix-like operating systems: Linux, Solaris, …

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debug : using iw command ( netlink debugging )

ABOUT Netlink The Netlink socket family is a Linux kernel interface used for inter-process communication (IPC) between both the kernel and userspace processes, and between different userspace processes, in a way similar to the Unix domain sockets. Similarly to the Unix domain sockets, and unlike INET sockets, Netlink communication cannot traverse host boundaries. However, while …

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send patches using git using yahoo mail server

ABOUT git Git (/ɡɪt/[7]) is a distributed version control system for tracking changes in source code during software development.[8] It is designed for coordinating work among programmers, but it can be used to track changes in any set of files. Its goals include speed,[9] data integrity,[10] and support for distributed, non-linear workflows. MAY BE CORRECT …

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tcp_rmem – vector of 3 INTEGERs: min, default, max

ABOUT tcp_rmem min: Minimal size of receive buffer used by TCP sockets. It is guaranteed to each TCP socket, even under moderate memory pressure. Default: 1 page default: initial size of receive buffer used by TCP sockets. This value overrides net.core.rmem_ default used by other protocols. Default: 87380 bytes. This value results in window of …

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