Posts Tagged ‘network’

How to use wget and curl via HTTP Proxy server / How to set a HTTPS proxy server on a bash shell on Linux

Wednesday, January 27th, 2016


I've been working a bit on a client's automation, the task is to automate process of installations of Apaches / Tomcats / JBoss and Java servers, so me and colleagues don't waste too
much time in trivial things. To complete that I've created a small repository on a Apache with a WebDav server with major versions of each general branch of Application servers and Javas.
In order to access the remote URL where the .tar.gz binaries archives reside, I had to use a proxy serve as the client runs all his network in a DMZ and all Web Port 80 and 443 HTTPS traffic inside the client network
has to pass by the network proxy.

Thus to make the downloads possible via the shell script, writting I needed to set the script to use the HTTPS proxy server. I've been using proxy earlier and I was pretty aware of the http_proxy bash shell
variable thus I tried to use this one for the Secured HTTPS proxy, however the connection was failing and thanks to colleague Anatoliy I realized the whole problem is I'm trying to use http_proxy shell variable
which has to only be used for unencrypted Proxy servers and in this case the proxy server is over SSL encrypted HTTPS protocol so instead the right variable to use is:


The https_proxy var syntax, goes like this:

export https_proxy="$proxy_url"


Once the https_proxy variable is set  UNIX's wget non interactive download tool starts using the proxy_url variable set proxy and the downloads in my script works.

Hence to make the different version application archives download work out, I've used wget like so:

 wget –no-check-certificate –timeout=5

For other BSD / HP-UX / SunOS UNIX Servers where  shells are different from Bourne Again (Bash) Shell, the http_proxy and  https_proxy variable might not be working.
In such cases if you have curl (command line tool) is available instead of wget to script downloads you can use something like:

 curl -O -1 -k –proxy

The http_proxy and https_proxy variables works perfect also on Mac OS X, default bash shell, so Mac users enjoy.
For some bash users in some kind of firewall hardened environments like in my case, its handy to permanently set a proxy to all shell activities via auto login Linux / *unix scripts .bashrc or .bash_profile that saves the inconvenience to always
set the proxy so lynx and links, elinks text console browsers does work also anytime you login to shell.

Well that's it, my script enjoys proxying traffic 🙂

Resume sftp / scp cancelled (interrupted) network transfer – Continue (large) partially downloaded files on Linux / Windows

Thursday, April 23rd, 2015

I've recentely have a task to transfer some huge Application server long time stored data (about 70GB) of data after being archived between an old Linux host server and a new one to where the new Tomcat Application (Linux) server will be installed to fit the increased sites accessibility (server hardware overload).

The two systems are into a a paranoid DMZ network and does not have access between each other via SSH / FTP / FTPs and even no Web Access on port (80 or SSL – 443) between the two hosts, so in order to move the data I had to use a third HOP station Windows (server) which have a huge SAN network attached storage of 150 TB (as a Mapped drive I:/).

On the Windows HOP station which is giving me access via Citrix Receiver to the DMZ-ed network I'm using mobaxterm so I have the basic UNIX commands such as sftp / scp already existing on the Windows system via it.
Thus to transfer the Chronos Tomcat application stored files .tar.gz archived I've sftp-ed into the Linux host and used get command to retrieve it, e.g.:


Connected to Linux-server.
sftp> get Chronos_Application_23_04_2015.tar.gz


The Secured DMZ Network seemed to have a network shaper limiting my get / Secured SCP download to be at 2.5MBytes / sec, thus the overall file transfer seemed to require a lot of time about 08:30 hours to complete. As it was the middle of day about 13:00 and my work day ends at 18:00 (this meant I would be able to keep the file retrieval session for a maximum of 5 hrs) and thus file transfer would cancel when I logout of the HOP station (after 18:00). However I've already left the file transfer to continue for 2hrs and thus about 23% of file were retrieved, thus I wondered whether SCP / SFTP Protocol file downloads could be resumed. I've checked thoroughfully all the options within sftp (interactive SCP client) and the scp command manual itself however none of it doesn't have a way to do a resume option. Then I thought for a while what I can use to continue the interrupted download and I remembered good old rsync (versatile remote and local file copying tool) which I often use to create customer backup stragies has the ability to resume partially downloaded files I wondered whether this partially downloaded file resume could be done only if file transfer was only initiated through rsync itself and luckily rsync is able to continue interrupted file transfers no matter what kind of HTTP / HTTPS / SCP / FTP program was used to start file retrievalrsync is able to continue cancelled / failed transfer due to network problems or user interaction activity), that turned even pretty easy to continue failed file transfer download from where it was interrupted I had to change to directory where file is located:

cd /path/to/interrupted_file/

and issue command:

rsync -av –partial .

the –partial option is the one that does the file resume trick, -a option stands for –archive and turns on the archive mode; equals -rlptgoD (no -H,-A,-X) arguments and -v option shows a file transfer percantage status line and an avarage estimated time for transfer to complete, an easier to remember rsync resume is like so:

rsync -avP .
receiving incremental file list
  4364009472   8%    2.41MB/s    5:37:34

To continue a failed file upload with rsync (e.g. if you used sftp put command and the upload transfer failed or have been cancalled:

rsync -avP chronos_application_23_04_2015.tar.gz

Of course for the rsync resume to work remote Linux system had installed rsync (package), if rsync was not available on remote system this would have not work, so before using this method make sure remote Linux / Windows server has rsync installed. There is an rsync port also for Windows so to resume large Giga or Terabyte file archive downloads easily between two Windows hosts use cwRsync.

Top AIX UNIX Performance tracking commands every Linux admin / user should know

Monday, March 16th, 2015


Though IBM AIX is basicly UNIX OS and many of the standard Linux commands are same or similar to AIX's if you happen to be a Linux sysadmin and you've been given some 100 AIX servers,  you will have to invest some time to read on AIX, however as a starter you should be aware to at least be able to do performance tracking on system to prevent system overloads. If that's the case I advise you check thoroughfully below commands documentation.

fcstat – Displays statistics gathered by the specified Fibre Channel device driver

filemon – Performance statistics for files, logical/physical volumes and virtual memory segments

fileplace – Displays the placement of file blocks within logical or physical volumes.

entstat – Displays the statistics gathered by the specified Ethernet device driver

iostat – Statistics for ttys, disks and cpu ipcs – Status of interprocess communication facilities

lsps – Statistics about paging space

netstat – Shows network status

netpmon – Performance statistics for CPU usage, network device-driver I/O, socket calls & NFS

nfsstat – Displays information about NFS and RPC calls

pagesize – Displays system page size ps – Display status of current processes

pstat – Statistics about system attributes

sar – System Activity Recorder

svmon – Captures a snapshot of the current contents of both real and virtual memory

traceroute – intended for use in network testing, measurement, and management.

tprof – Detailed profile of CPU usage by an application vmstat – Statistics about virtual memory and cpu/hard disk usage

topas – AIX euqivalent of Linux top command

Here are also useful examples use of above AIX performance tracking commands

To display the statistics for Fiber Channel device driver fcs0, enter:

fcstat fcs0

To monitor the activity at all file system levels and write a verbose report to the fmon.out file, enter:

filemon -v -o fmon.out -O all

To display all information about the placement of a file on its physical volumes, enter:

fileplace -piv data1

To display a continuous disk report at two second intervals for the disk with the logical name disk1, enter the following command:

iostat -d disk1 2

To display extended drive report for all disks, enter the following command:

iostat -D

To list the characteristics of all paging spaces, enter:

lsps -a

List All Ports (both listening and non listening ports)

netstat -a | more

The netpmon command uses the trace facility to obtain a detailed picture of network activity during a time interval.

netpmon -o /tmp/netpmon.log -O all;

netpfmon is very much like AIX Linux equivalent of tcpdump To print all of the supported page size with an alphabetical suffix, enter:

pagesize -af

To display the i-nodes of the system dump saved in the dumpfile core file

pstat -i dumpfile

To report current tty activity for each 2 seconds for the next 40 seconds, enter the following command:

sar -y -r 2 20

To watch system unit for 10 minutes and sort data, enter the following command:

sar -o temp 60 10

To report processor activity for the first two processors, enter the following command:

sar -u -P 0,1

To display global statistics for virtual memory in a one line format every minute for 30 minutes, enter the following command:

svmon -G -O summary=longreal -i 60 30

The traceroute command is intended for use in network testing, measurement, and management. While the ping command confirms IP network reachability, you cannot pinpoint and improve some isolated problems

traceroute aix1

Basic global program and thread-level summary / Reports processor usage

prof -x sleep 10

Single process level profiling

tprof -u -p workload -x workload

Reports virtual memory statistics

vmstat 10 10

To display fork statistics, enter the following command:

vmstat -f

To display the count of various events, enter the following command: vmstat -s To display the count of various events, enter the following command:

vmstat -s

To display time-stamp next to each column of output of vmstat, enter the following command:

vmstat -t

To display the I/O oriented view with an alternative set of columns, enter the following command:

vmstat -I

To display all the VMM statistics available, enter the following command:

vmstat -vs

If you already have some experience with some BSD (OpenBSD or FreeBSD) you will feel much more confortable with AIX as both operating system share common ancestor OS (UNIX System V), actually IBM AIX is U. System V with 4.3 BSD compatible extensions. As AIX was the first OS to introduce file system journalling, journalling capabilities on AIX are superb. AIX was and is still widely used by IBM for their mainframes, on IBM RS/6000 series (in 1990s), nowdays it runs fine on PowerPC-based systems and IA-64 systems.
For GUI loving users which end up on AIX try out SMIT (System Management Interface tool for AIX). AIX was using bash shell in prior versions up to AIX 3 but in recent releases default shell is Korn Shell (ksh88).
Nowdays AIX just like HP-UX and rest of commercial UNICes are loosing ground as most of functionalities is provided by commercial Linux distributions like RHEL so most of clients including Banks and big business clients are migrating to Linux.

Happy AIX-ing ! 🙂

How to share your Windows local drives via Remote Desktop (RDP) – Safe file copy with RDP protocol

Tuesday, October 14th, 2014


Just had a task to install Tomcat 7, Java JRE 1.7 and .NET Framework 3.5 and MS Visual C++ x86 on a Windows 2008 RC2 system situated behind a firewalled network NAT. To do the installation I had to use a special jump host (which was also a MS Windows system). The end system where installation had to occur did not have access to the Internet was in special DMZ-ed network so to install above 3 software packages I had to transfer them from my notebook to install host.
To depic what had to happen, I had to:

Transfer files from (host A – my notebook) -> via host (B – jump host) to host (C – the end install host).

Default Windows RDP Client command (mstsc.exe) supports transferring files between host A and RDP-ed host B via standard file copy / paste, so I tried transferring files between my work Windows PC to (jump host B), by copy pasting the files, but as the DotNetFx35Client.exe file was 261 Megabytes and the network between host A and B has some shapings and network firewalls the file transfer timed out. Copy / Paste method via RDP Protocol by default, doesn’t support Transfer Resume thus in order to transfer the 261 MB file, I tried Sharing C:Temp Folder and transfer that way, but unfortunately I didn’t have the permissions in that Windows Domain to create sharings (even though on the remote system I was already logged in with admin accounts). I’ve consulted a colleague on advise on how to transfer the files and I was told about a Win RDP client option to share drives.

Here is how to share your PC drive letters C: D: E: etc. via Remote Desktop Protocol

1. Run mstsc.exe

2. Click the Options button


3. Click Local Resources tab

4. Click More button


5. Click on Drives


Then after connecting to the Remote RDP host, all your local PC drive partitions C: D: E: will be visible as (attached) ones in mounted in My Computer / MS Explorer with assigned new drive letters

Once, I transferred the .NET Framework 3.5 while using the installer I was notified that .NET Framework 3.5 is by default included in Windows 8 and I need only to enable it.

To enable .NET Framework 3.5 in Windows 8 from Control Panel

Choose Programs, and then choose Turn Windows features on or off.

Select the .NET Framework 3.5 (includes .NET 2.0 and 3.0) check box.

Create local network between virtual machines in Virtualbox VM – Add local LAN between Linux Virtual Machines

Wednesday, June 11th, 2014


I want to do test MySQL Cluster following MySQL Cluster Install Guide for that purpose, I've installed 2 version of CentOS 6.5 inside Virtualbox and I wanted to make the 2 Linux hosts reachable inside a local LAN network, I consulted some colleagues who adviced me to configure two Linux hosts to use Bridget Adapter Virtualbox networking (Network configuration in Virtualbox is done on a Virtual Machine basis from):

Devices -> Network Settings

(Attached to: Bridged Adapter)

Note!: that by default Cable Connected (tick) is not selected so when imposing changes on Network – tick should be set)
After Specifying Attached to be Bridged Adapter to make CentOS linux refresh network settings run in gnome-terminal:

[root@centos ~]# dhclient eth0

However CentOS failed to grab itself DHCP IP address.
Thus I tried to assign manually IP addresses with ifconfig, hoping that at least this would work, e.g.:

on CentOS VM 1:

/sbin/ifconfig eth0 netmask

on CentOS VM 2:

/sbin/ifconfig eth1 netmask

To test whether there is connection between the 2 VM hosts tried ping-ing (from and tested with telnet if I can access remotely SSH (protocol), from CentOS VM2 1 to CentOS VM2 and vice versa, i.e.:

[root@centos ~]# telnet 22


telnet: connect to address No route to host

Then after checking other options and already knowing by using VBox NAT network option I had access to the internet, I tried to attach a standard local IP addresses to both Linux-es as Virtual interfaces (e.g eth0:1), .e.g:

On Linux VM 1:

/sbin/ifconfig eth0:0 netmask

On Linux VM 2:

/sbin/ifconfig eth1:0 netmask

Then to test again used telnet

[root@centos ~]# telnet 22

Then I found Virtualbox has a special Internal Networking support

to choose in Attached to drop down menu. According to Internal Networking Virtualbox instructions to put two Virtual Machine hosts inside an Internal network they should be both set in Internal network with identical name.
P. S. It is explicitly stated that using Internal Network will enable access between Guest Virtual Machines OS, but hosts will not have access to the Internet (which in my case doesn't really mattered as I needed the two Linux VMs just as a testbed)


I tried this option but it doesn't work for me for some reason, after some time of research online on how to create local LAN network between 2 Virtual Machines luckily I decided to test all available Virtualbox Networking choices and noticed Host-only adapter.

Selecting Host-only Adapter and using terminal to re-fetch IP address over dhcp:


On CentOS VM1

dhclient eht0

On CentOS VM2

dhclient eth1

assigned me two adjoining IPs – ( and

Connection between the 2 IPs and on TCP and UDP and ICMP protocol works, now all left is to install MySQL cluster on both nodes.


What is IPMI (IPKVM), ILO and IDRAC – Remote management interfaces to server / PC on BIOS level

Friday, May 30th, 2014

Intelligent Platform Management Interface is a standardized computer interface also accessible remotely via Java applet allowing remote management and monitoring access to PC BIOS. IPMI is a way to manage a computer that may be powered off or otherwise unresponsive by using a network connection to the hardware rather than to an operating system or a keyboard physical / screen login shell. The IPMI server standard was introduced by Intel and nowadays supported by more than 200 computer vendors i.e. – Super Micro, Hewlett Packard, Cisco, Dell etc.

Intelligent Platform Management Interface is an open, industry-standard interface that was designed for the management of server systems over network. IPMI interfaces by various vendors have also Virtual Media support (i.e. – Operating System  ISO files could be mounted remotely to a Virtual CD / DVD rom and you can approach installing a bare-metal server without physical presense to it). Just like Power Off / Restart, BIOS Entrance and Virtual Media access is done directly through a web-browser interface over the network or the internet.


ILO – stands for Integrated Lights-Out and is  HP Proliant servers remote console to PC / server physical screen. ILO is server integrated chip on HP servers and doesn't need further installations. It gives you a web console using Java showing you server screen just like there is a Monitor connected to the server it is precious for remote system administration purposes as often when there is no SSH  or Remote Desktop to server you can see directly whether the server has completed hanged and try to recover or see a failing hardware notification on the screen to a server with a partially accessible services. Using ILO console access to an HP server one can have a BIOS access remotely to machines already colocated in data canters. In other words ILO is HP's variation of IPMI remote interface also known under business buzz word IPKVM.


DRAC (iDRAC)- Dell's Remote Access Controller is interface card from Dell Inc. offering remote access (out-of-band) management facilities – i.e. DRAC is Dell's variant of HP's ILO – an implementation of Intel's IPMI out-of-band standard. DRAC is also giving you remote way to access no other means accessible server on a software level. Interesting and nice things is Dell provides their DRAC source code, so if you're a developer you can learn how DRAC technology works on a lower level.

ILO, iDRAC (Dell's new generation DRAC for Blade servers) and ILO's remote management interfaces's (IPMI tools) most valuable features is it allows remote system Power On / Shutdown and Remote Restart while monitoring the server screen (hardware output) messages and allowing you see critical hardware issue messages on pre-OS boot time, failure with memory, hard disks etc. and remote interface to do BIOS tuning.

MobaXTerm: A good gnome-terminal like tabbed SSH client for Windows / Windows Putty Tabs Alternative

Wednesday, November 13th, 2013

Mobaxterm ssh client putty MS Windows alternative with tabs suitable for ex linux users

mobaxterm with tabbed ssh connections screenshot best putty windows ssh client alternative now

Last 10+ years I worked on GNU / Linux as Desktop. Last 7 years most of my SSH connections were managed from GNOME and I'm quite used to gnome-terminal ssh tabbing. In my new Employee Hewlett Packard. I'm forced to work on Microsoft Windows 7 and thus I used for a month or so Putty and Kitty fork from version 0.63 of PuTTY advertising itself as the best telnet / SSH client in the world. Both of the two lack tabbing and have interface which is pretty unfamiliar to me. As I'm so used to using native UNIX terminal. Fortunately a colleague of mine Ivelin was using an SSH client called MobaXTerm which very much did emulation similar to my favourite gnome-terminal. MobaXterm is not free software / open source app but this doesn't matter so much to me as anyways I'm running a non-free Win OS on my desktop. What makes MobaXterm so attractive is its rich functionality (cosmic years infront of Putty).

Here is website description of MobaXterm quoted from its website:

MobaXterm is an enhanced terminal for Windows with an X11 server, a tabbed SSH client and several other network tools for remote computing (VNC, RDP, telnet, rlogin). MobaXterm brings all the essential Unix commands to Windows desktop, in a single portable exe file which works out of the box.

Overall list of features MobaXterm offers are;

  •     multitab terminal with embedded Unix commands (ls, cd, cat, sed, grep, awk, rsync, wget, …)

  •     embedded X11 server for easily exporting your Unix/Linux display

  •     a session manager with several network utilities: SSH, RDP, VNC, Telnet, Rlogin, FTP, SFTP and XDMCP

  •     passwords management for SSH, RDP, VNC, SFTP (on demand password saving)

  •     easy graphical file transfer using drag and drop during SSH sessions

  •     advanced SSH tunnels creation tool (graphical port forwarding builder)

  •     tasks automation using scripts or macros

Mobaxterm is portable just like Putty so its useful to use on HOP stations to servers like used in big companies like HP. Featured embedded Unix commands (e.g., ls, cd, cat, sed, grep, awk, rsync, wget) gives a feeling like you're working on pure Linux console making people addicted to Linux / BSD quite confortable. Some other very useful terminal emulator functions are support for anti-aliasing session manager (save / remember passwords for ssh sessions in Crypted format so much missing in Putty) and it even supports basic macros.
Basic UNIX commands embedded in MobaXterm are taken and ported from Cygwin projectLinux-like environment for Windows making it possible to port software running on POSIX systems (such as Linux, BSD, and Unix systems) to Windows. A very cool think is also MobaXterm gives you a Linux like feel of console navigation in between basic files installed from Cygwin. Some downside I found is program menus which look at first glimpse a bit confusing especially for people used to simplicity of gnome-terminal. Once logged in to remote host via ssh command the program offers you to log you in also via SFTP protocol listing in parallel small window with possibility to navigate / copy / move etc. between server files in SFTP session which at times is pretty useful as it saves you time to use some external SFTP connector tools like  WinSCP.

From Tools configuration menu, there are few precious tools as well;
         – embedded text editor MobaTextEditor
         – MobaFoldersDiff (Able to show diffeernces between directories)
         – AsciiTable (Complete List of Ascii table with respective codes and characters)
         – Embedded simple Calculator
         – List open network ports – GUI Tool to list all open ports on Windows localhost
         – Network packets capture – A Gui tool showing basic info like from UNIX's tcpdump!
         – Ability to start quickly on local machine (TFTP, FTP, SFTP / SSH server, Telnet server, NFS server, VNC Server and even simple implementation of HTTP server)

Mobaxterm list of tools various stuff

         Mobaxterm run various services quickly on Windows servers management screenshot

Below are few screenshots to get you also idea about what kind of configuration MobaXterm supports
  mobaxterm terminal configuration settings screenshot

mobaxterm better putty alternative x11 configuration tab screenshot

mobaxterm windows ssh client for linux users configuration ssh tab screenshot

MobaXTerm Microsoft Windows ssh client configuration misc menu screenshot
To configure and use Telnet, RSH, RDP, VNC, FTP etc. Sessions use the Sessions tab on top menu.

One very handy thing is MobaXterm supports export of remote UNIX display with no requirement to install special Xserver like already a bit obsolete Xming – X server for Windows.
The X Display Manager Control Protocol (XCMCP) is a key feature of the X11 architecture. Together with XDMCP, the X network protocol allows distributed operation of the X server and X display manager. The requesting X server runs on the client (usually as an X terminal), thus providing a login service, that why the X server ported to MobaXterm from Cygwin also supports XDMCP. If, for example, you want to start a VNC session with a remote VNC server, all you have to do is enter the remote VNC server’s IP address in the VNC area; the default VNC port is already registered.

Accessing the remote Windows server via RDP (Remote Desktop Protocol) is also a piece of cake. Once you establish a session to RDP or other Proto it is possible to save this session so later you just choose between session to access. The infamous (X11 Port Forwarding) or creation of SSH encrypted tunnels between hosts to transfer data securily or hide your hostname is also there.

MobaXterm is undoubtedly a very useful and versatile tool. Functionally, the software is well mannered, and Windows users who want to sniff a little Linux/Unix air can get a good idea of how Linux works. A closer look reveals that anything you can do with MobaXterm can be achieved directly with freely available tools (Cygwin) and Unix tools ported from Cygwin. However, although Cygwin provides a non-Posix environment for Windows, it doesn’t offer a decent terminal, which is one thing Moba-Xterm has going for it.

Admittedly, in pure vanilla Cygwin, you can start an X server automatically and then use xterm, but xterm lacks good-quality fonts, whereas MobaXterm conveniently lets you integrate a font server.

How a Ponzi Scheme works – Ponzi the most famous fraudulent network

Monday, March 4th, 2013


Those who are living in ex-communist countries who have been through the so called "Perestroika" – Pre-structuring of economy and in the so called privatization process which is selling factories, land and whateve in a country to a private sector business investors have already experienced the so called "Pyramidal" structure businesses which at the end collapse and left after itself a tens of thousands of cheated "investors" without their capital money. In my homeland Bulgaria, during this pre-structuring which in practice was "destructioning" there was thousands of companies for a very long period of time who somehow used this pyramidal structures to steal people investments which already melted in times because of the severe inflation that invaded the country. Near my city in Dobrich. There was a company called Yugoagent started by a "serbian Pharaoh – a charlatan CEO" whose company was promising extraordinary profit interest for people who invested money in Yugoagent as well as big reduction of prices of all investors to purchase "white technigue" home equipment from Yugoagent stores. What happened was maybe between 10 000 to 30 000 of people because "investors" to Yugoagent led only by the blind faith and personal desire to earn. The interest offered by Yugoagent was more than 10% to money put in, I believe he was offering 30% of interest or so and people easily get into the trap of his pre-determined to collapse company. What happened after was Mirolub Gaich's company survived for few years while some of the "investors" ripped benefits, where the multitude just lost their money because of epochal bankruptcy of YUGOAGENT.… I know even some of my relatives has been fooled into the obvious fraudulent business, because our society in Bulgaria lived in communism and was not prepared to face the sad reality of money only centered economy – the so loudly proclaimed as "just" democracy.

Today there are plenty of companies around the world still opened and operated under the same fraudulent model leaving after their bankruptcy their makers with millions in banks smartly stolen and claimed as company losses right before the collosal company collapse. A friend of mine Zlati, took the time to invest some time to research more into how this fraudulent Scheme works and found some references to wikipedia which explains the Scheme in details. Thus I also red a bit and thought my dear readers might be interested to know also how the scheme works. I believe it is a must for anyone who has the intention to be in business. It is good to know to escape the trap, cause even in Pro and High profit businesses there are companies operating under the same hood. Today there are plenty of online based companies today who are somehow involved into Offshore business or even do some kind of money laundry frauds, while offering beneficial investments in a booming companies. It is useful for even ordinary people to get to know the fraudulent scheme to escape from it. With the worsening crisis, the fraudulent activities and companies that does some kind of fraud to make profit increased dramatically and thus the old but well known fraudulent model is blooming.


How Ponzi scheme works explained in 5 minutes

To know a bit more about the Ponzi scheme as well as the so called "Pyramid" based fraudulent business check in Wikipedia Ponzi scheme

For those lazy to read in Wikipedia, here is extract from it explaining the Ponzi fraudulent Scheme in short

A Ponzi scheme is a fraudulent investment operation that pays returns to its investors from their own money or the money paid by subsequent investors, rather than from profit earned by the individual or organization running the operation.
The Ponzi scheme usually entices new investors by offering higher returns than other investments, in the form of short-term returns that are either abnormally high or unusually consistent. Perpetuation of the high returns requires an ever-increasing flow of money from new investors to keep the scheme going The system is destined to collapse because the earnings, if any, are less than the payments to investors. Usually, the scheme is interrupted by legal authorities before it collapses because a Ponzi scheme is suspected or because the promoter is selling unregistered securities. As more investors become involved, the likelihood of the scheme coming to the attention of authorities increases. The scheme is named after Charles Ponzi, who became notorious for using the technique in 1920.
Ponzi did not invent the scheme (for example, Charles Dickens' 1844 novel Martin Chuzzlewit and 1857 novel Little Dorrit each described such a scheme),[ but his operation took in so much money that it was the first to become known throughout the United States. Ponzi's original scheme was based on the arbitrage of international reply coupons for postage stamps; however, he soon diverted investors' money to make payments to earlier investors and himself.

How to change order of network cards eth0 and eth0 (swap lan cards) on Debian GNU / Linux

Friday, September 21st, 2012

Swap eth0 and eth1 lan card / how to change network card order on Debian Gnu / linux

I have a Debian server with 2 network adapter cards – (eth0 and eth1). The first lan card eth0 is Mainboard embedded (integrated) one.

The hardware of the Lenovo ThinkCentre host was purchased with one LAN Card but a second one was added in order to make the machine capable of doing NAT routing with iptables.

The machine is to be configured as a router in 1st lan card eth0, an internet UTP cable should influx and the 2nd lan card is to be connected to a Network Switch and will be used to NAT network traffic from the internal network of number of hosts with assigned local IP addresses like ( – 255) etc.

Everyone knows that integrated Network cards, are usually inferior to the normal non-integrated ones and besides that if a high voltage (during Weather Storm) enters through UTP cable attached to the integrated LAN Card it is quite likely the whole Mainboard to burn out …

With saying this back to my case I had to make the Internet to connect on eth0 on a Debian Linux host which was supposed to run as a Network router. As eth0 was the one where I had to configure the Internet real IP address to be assigned, I preferred eth0 to be attached to the non-integrated Ethernet Card which was automatically recognized and assigned to be eth1 by kernel.

Therefore I needed to swap interfaces eth0 and eth1, here is how this is done on Debian GNU / Linux Squeeze (6.0.5):

1. Edit /etc/udev/rules.d/70-persistent-net.rules

# vim /etc/udev/rules.d/70-persistent-net.rules

The file content should look something similar to:

# This file was automatically generated by the
# program, run by the persistent-net-generator.rules rules file.
# You can modify it, as long as you keep each rule on a single
# line, and change only the value of the NAME= key.
# PCI device 0x10ec:0x8168 (r8169)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*",
ATTR{address}=="90:f6:C2:3d:76:f5", ATTR{dev_id}=="0x0",
ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"
# PCI device 0x10ec:0x8168 (r8169)
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*",

ATTR{address}=="8d:89:a5:c2:e8:f8", ATTR{dev_id}=="0x0",

ATTR{type}=="1", KERNEL=="eth*", NAME="eth1"

Swap eth0 and eth1 definitions so eth0 becomes eth1 and vice versa, e.g.:

SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*",

ATTR{address}=="8d:89:a5:c2:e8:f8", ATTR{dev_id}=="0x0",

ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"
SUBSYSTEM=="net", ACTION=="add", DRIVERS=="?*",
ATTR{address}=="90:f6:C2:3d:76:f5", ATTR{dev_id}=="0x0",
ATTR{type}=="1", KERNEL=="eth*", NAME="eth1"

ATTR{type}=="1", KERNEL=="eth*", NAME="eth0"

To make udevd, reassign eth0 / eth1 cards orders restart udev daemon:

# /etc/init.d/udev restart

or restart the system, i.e.

# restart

That should swap the Lan card order as recognized by Linux. Cheers 😉