Vagrant – build always same VMs

Vagrant is a tool for building complete development environments.

With an easy-to-use workflow and focus on automation, Vagrant lowers development environment setup time, increases development/production parity, and makes the “works on my machine” excuse a relic of the past.

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Ansible automation

Ansible is App deployment, configuration management and orchestration – all from one system.

It uses no agents and no additional custom security infrastructure, so it’s easy to deploy – and most importantly, it uses a very simple language (YAML, in the form of Ansible Playbooks) that allow you to describe your automation jobs in a way that approaches plain English. Continue reading

Cisco CEF packet forwarding

Routers support three packet-forwarding mechanisms:

  • Process switching – Legacy method, each packet that arrives on an interface, is forwarded to the control plane where the CPU matches the destination address with an entry in its routing table, then determines the exit interface and forwards the packet via out interface. This is done for each packet even if the destination in the stream is the same Continue reading

History of Internet everyone should know

  • 1969 – the first message is transmitted from SDS Sigma 7 mainframe computer at University of California, Los angeles (UCLA) to an SDS 940 mainframe computer at Stanford Research Institute
  • 1970 – ALOHAnet becomes operational, the first packet radio network, developed by Norman Abramson, University of Hawaii
  • 1972
    • Ray Tomlinson chooses the @ sign to signify the recipient’s destination
    • Larry Roberts writes the first email management program
    • Telnet specification written (RFC 318)
  • 1981 – the TCP and IP protocols are formalized (RFC 793 and RFC 791)
  • 1984 – Domain Name Service (DNS) is introduced
  • 1985 – File Transfer Protocol (FTP) is documented (RFC 765)
  • 1991 – Tim Berners-Lee and Robert Cailliau release the specifications for WWW
  • 1993 – the first web browser MOSAIC, is developed by Marc Andreessen at the University of Illinois, Champaign-Urbana
  • 1995 – the first specification for IPv6 released (RFC 1883)
  • 2011 – the first World IPv6 Day (June 8), including Google, Facebook and Yahoo with more than 1000 other companies participated for a worldwide trial of IPv6

TCP/IP

The first packet switching network and predecessor to today’s Internet was the Advanced Research Projects Agency Network (ARPANET), which came to life in 1969 by connecting mainframe computers at four locations. ARPANET was funded by the U.S. Department of Defense for use by universities and research laboratories. Bolt, Beranek and Newman (BBN) was the contractor that did much of the initial development of the ARPANET, including creating the first router known as an Interface Message Processor (IMP).

In 1973, Robert Kahn and Vinton Cerf began work on TCP to develop the next generation of the ARPANET. TCP was designed to replace ARPANET’s current Network Control Program (NCP). In 1978, TCP was divided into two protocols: TCP and IP. Later, other protocols were added to the TCP/IP suite of protocols including Telnet, FTP, DNS, and many others.

Ethernet

Ethernet was a protocol originally developed by Bob Metcalfe at the XEROX Palo Alto Research Center (PARC) in the 1970s. In 1979, Bob Metcalfe formed his own company, 3COM, and worked with Digital Equipment Corporation (DEC), Intel, and Xerox to promote the “DIX” standard for Ethernet. In 1985, the Institute of Electrical and Electronics Engineers (IEEE) published the IEEE 802.3 standard that was almost identical to Ethernet. Today, 802.3 is the common standard used on local-area networks (LANs).

Bootable USB in linux with freeDOS

Bootable USB stick is very handy and it seems to easy to create using dedicated applications both under Linus or M$ but let’s set the challenge and try to make it manually from the bare Linux command like. This knowledge may become very helpful in Data Centrer scenarios  where servers BIOS need to be updated but no Windows environment is available for the M$ executable to run.

At the end of this tutorial you will see that USB creators tools are quite sophisticated peace of software allowing to create many different systems  with a speed of blink of an eye not necessary telling to the user all magic happening under a hood. Let’s start… Continue reading

Conky alternative in M$ – Desktopinfo

In Linux we have Conky in Windows Desktopinfo or BGinfo. Here below I would like to propose to use Desktopinfo. This is not as much of use for home users to extend their desktop by beatutifult intergated system info direct with the desktop wallpaper / background. The most common use would be for multiple M$ systems hosted in cloud, small business servers or farms where you remote often and want to have all the system info right on plate – on your background. This saves time thus increase performance of administrative tasks by easy visually identifying the system health and resources. Continue reading