VPS : Virtual Private Server

What is a Virtual Private Server?

A Virtual Private Server (VPS) is an entire operating system that runs within another operating system. It will share system resources like the CPU and RAM with other users but the resources are allocated in such a way that you cannot tell that the system has anyone else on it, much like a dedicated server. So resources are usually setup in such a way that each hosting client is only allowed to use an allocated percent, meaning that resources assigned to you will always available to you. Each virtual server looks and acts like a dedicated server.
So for instance, there may be a server with 2GB RAM, 100GB of disk space and 2 x 2GHz processors with 10 VPSes on it. Each one is guaranteed to have access to 200MB RAM, a disk space limit of 10GB, and an effective CPU of 400Mhz.

There are a number of virtualization technologies, which make this all possible. There are commercial companies such as http://www.vmware.com VMWare, http://www.xensource.com/ XEN.

Like an emulator, VMware software provides a completely virtualized set of hardware to the guest operating system. VMware software virtualizes the hardware for a video adapter, a network adapter, and hard disk adapters. The host provides pass-through drivers for guest USB, serial, and parallel devices.

In essence, virtualization lets you transform hardware into software. Use software such as VMware ESX Server to transform or virtualize the hardware resources of an x86-based computerincluding the CPU, RAM, hard disk and network controllerto create a fully functional virtual machine that can run its own operating system and applications just like a real computer.

Multiple virtual machines share hardware resources without interfering with each other so that you can safely run several operating systems and applications at the same time on a single computer.

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OSI Layer

IMPORTANCE OF OSI LAYERS IN NETWORKING

Network
A network is an interconnection of 2 or more devices in order to communicate with each other.

OSI (Open Systems Interconnection)
-To divide complicated process of networking into different layers.
-To allow different vendors networks to interoperate.
-Developing protocols and devices for different layers.
-OSI reference model was introduced by international organization for standardization (ISO).
-It allows various types of network hardware and software to communicate. Continue reading…

Future webhosting

Introduction

How different will be the kind of future web hosting ? With day by day betterment in technological aspects ,one thing is sure the hardware aspects will be quiet sound that, the processing capability , RAM memory e.t.c may multiples of 10?s of Giga Bytes or more e.t.c
Will that means that there wont be any congestion problems , or problems like sever going down e.t.c, That future is not far away.sure Intels Dual processing system can be considered as a small step towards this. Below are few other concepts towards this.

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CACTI

About Cacti

Cacti is a PHP/MySQL front end to rrdtool. It handles the storage of all the information required to create and populate rrdtool graphs. Along with being able to maintain Graphs, Data Sources, and RoundRobin Archives in a DataBase, Cacti handles the data gathering also. There is also SNMP support for those used to creating traffic graphs with MRTG.
You can use Cacti to gather any sort of data, or fetch information from SNMP capable hosts.

To manually handle data gathering, you can feed Cacti the Command Line for any external script/command along with any data that the user will need to fill in (IP addresses etc). Cacti will then gather this data in a cron job and populate a MySQL database/the RoundRobin Archives.
Data Sources can also be created, which correspond to actual data on the graph. For instance, if a user wants to graph the ping times to a host, they could create a data source, choosing a script that pings a host and returns its value in milliseconds. After defining options for rrdtool such as how to store the data you will be able to define any additional information that the data input source requires, such as a host to ping in this case. Once a data source is created, it is automatically maintained at 5 minute intervals.
For people who are used to creating traffic graphs in MRTG, this process has become much simpler in Cacti. An SNMP interface allows you to enter SNMP capable hosts and Cacti will display that hosts interfaces, all of which can be graphed with once click from that point.
Once one or more data sources are defined, an rrdtool graph can be created using the data. Cacti allows you to create almost any imaginable rrdtool graph using all of the standard rrdtool graph types and consolidation functions. A color selection area and automatic text padding function also aid in the creation of graphs to make the process easier.
Cacti has a user management system so you can allocate people various levels of access to the program and their own settings.

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