Ajitabh Pandey's Soul & Syntax

Exploring systems, souls, and stories – one post at a time

Category: Published Articles

  • DeleGate – A Multi-platform, Multi-purpose Proxy Server

    Introduction

    A proxy server works as an intermediary for requests from clients seeking resources from other servers. There are various types of proxy servers. In this article we will be breifly discussing some of the capabilities of DeleGate.

    DeleGate is a multi-platform and multi-purpose general purpose proxy server which runs on Unix, Windows, MacOSX and OS/2. It allows various protocols to pass through it and apply cache and conversion to the pass-through data, access control and routing. Some of the protocols supported by delegate are – HTTP, FTP, NNTP, SMTP, POP, IMAP, LDAP, Telnet, SOCKS, DNS etc. DeleGate can also translate protocol between clients and server such as converting IPv4and IPv6. Multiple servers can be combined to look as single server using aliasing and filtering capabilities of DeleGate. For various automated purposes, DeleGate can also be used as an origin server for HTTP, FTP and NNTP.
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  • Creating VPNs with OpenVPN

    Introduction

    A VPN is a set of tools which allow networks at different locations to be securely connected, using a public network as the transport layer. A VPN produces a virtual “dedicated circuit” over the internet and use cryptography to secure it.
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  • Balancing Traffic Across Data Centres Using LVS

    The LVS (Linux Virtual Server) project was launched in 1998 and is meant to eliminate Single Point of Failures (SPOF). According to the linuxvirtualserver.org website: “LVS is a highly scalable and available server built on a cluster of real servers, with the load balancer running on Linux. The architecture of the server cluster is fully transparent to the end user, and the users interact as if it were a single high-performance virtual server. The real servers and the load balancers may be interconnected by either a high speed LAN or by a geographically dispersed WAN.”
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  • Building A Highly Available Nginx Reverse-Proxy Using Heartbeat

    A cluster in computing is a term used to describe a group of closely linked computers often appearing as a single entity to the outside world. There are various types of clusters—high-availability (HA) clusters, load-balancing clusters, compute clusters or high performance computing (HPC) clusters and grids.

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  • Building A Highly-Available Web Server Cluster

    nginx (pronounced as ‘engine x’) is a powerful HTTP Web server/reverse proxy and IMAP/POP3 reverse proxy. According to a survey conducted in December 2008 by Netcraft, nginx has grown significantly and has surpassed lighttpd (also known as Lighty). Because of its small memory footprint and high scalability, nginx has found tremendous usage in virtual private servers (VPS).

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