Who Writes Linux and Who Supports It

• Who is Writing Linux?

* Every Linux kernel is being developed by nearly 1,000 developers working for more than 100 different corporations. This is the foundation for the largest distributed software development project in the world.
* Since 2005, the number of active kernel developers has tripled, reflecting the growing importance of Linux in the embedded systems, server, and desktop markets.
* Between 70 and 95 percent of those developers are being paid for their work, dispelling the “hobbyist” myth present from the start of open source development.

• Who is Sponsoring Linux?

More than 70 percent of total contributions to the kernel come from developers working at a range of companies including IBM, Intel, The Linux Foundation, MIPS Technology, MontaVista, Movial, NetApp, Novell and Red Hat. These companies, and many others, find that by improving the kernel they have a competitive edge in their markets.

• How Fast is Linux Developed and Released?

* An average of 3,621 lines of code are added to the kernel tree every day, and a new kernel is released approximately every 2.7 months.
* The kernel, since 2005, has been growing at a steady state of 10 percent per year.

Linux XP Desktop 2008

Its a simple, reliable and user-friendly system

In the modern dynamically changing world with wide business and personal communications are very important for feeling assured and to have habitual, reliable and comfortable tools for work and communications.

Quickly growing sector of IT-decisions offers set of variants similar tools, but comfort and satisfaction from use similar tools it is not always equal to your expenses for their purchase.

We consider, that modern technologies have reached that level, when the program becomes not simply technical set of bits, and turns in work of art in which it would be desirable to take pleasure everyone minute of work with it. Therefore, we offer for you ergonomic, comfortable and functional workplace � Linux XP Desktop.

Linux XP Desktop makes your computer virus-free, stable and dependable. You'll spend less time fixing your PC and more time using a standard well-known graphical interface to get work done.

* The most user-friendly interface ever made for Linux
* Simple and clear installation and Windows-style setup tools
* Full set of applications for work in the Internet.
* Support of Microsoft Office document formats (WORD, EXCEL and others)
* Useful tools for working with Windows networks and VPN
* Full control of your computer, data and applications
* Stable, dependable and without any reinstallation
* Absolutely virus-free environment
* Free updates through a simple but useful interface (no RPM knowledge is required)

You will always know what programs are running and forget about viruses. A set of Windows-like setup tools allows you to perform system management duties in a way that is familiar to you.

To start working with Linux XP Desktop, your Windows-experience is all you need. You do not have to read tons of files on your screen, buy mountains of manuals, search the Internet for answers or call your Linux-guru every hour for help. Just install Linux XP Desktop and use it.

For More Information Click Here

How can I enable theme support in Windows Server 2003?

Windows Server 2003 has the theme support services disabled by default.

To enable themes on Windows Server 2003 follow the next steps:

1. Go to the Services applet in Administrative Tools (or click Start, then Run, and type "services.msc" (without quotes) and click
   OK).
2. Find the "Themes" service, right-click and select Properties, select "Automatic" instead of "Disabled" in the startup type box.
3. Click Apply.
4. Right-click the Themes service and select Start.
   

You can also modify start state and start it from a Command Prompt console by using the following command:
sc config Themes start= auto
sc start Themes (or net start Theme)

For now you only have Luna Blue, Silver and Olive Green to choose from.

1. Go to Control Panel, select Display and then go to the Appearance tab.
2. In the "Windows and Buttons" drop-down list select "Windows XP Style". Click Ok.
3. Now you can choose the color scheme.

Google phone coming in October

T-Mobile is about to launch the first phone based on Google's Android design. It hopes the new device will compete with Apple's iPhone.

This smartphone will be manufactured by High Tech Computer, a Taiwan-based company. It will have a large touch screen that slides out to reveal a five-row QWERTY keyboard. The device, which will be called the G1, will sell for $150 to T-Mobile customers in the first week of launch before it is offered to other customers at a higher price.

Google developed the Android design to help it expand its successful advertising business into the increasingly lucrative mobile market. It released the parameters to an alliance of mobile phone carriers, developers and manufacturers earlier this year.

Deutsche Telecom's T-Mobile announced in February that it would introduce Android-based phones in the fourth quarter of 2008.

How to change IP address from the Windows command line

To do the same thing via the command line, use the netsh tool.

After some experimentation, I found that the following two commands were sufficient to give my machine a static IP address and have everything still work ok. The "interface ip set address" command changes the IP to 192.168.1.101 (this address is outside the range allocated by our DHCP server, therefore it will be different to what we had before) and I also had to provide the subnet mask (255.255.255.0), default gateway (192.168.1.5) and a gateway metric. The second command explicitly sets the DNS server to use for name resolution - normally this is done for us by the DHCP server.

netsh interface ip set address "Local Area Connection" static 192.168.1.101 255.255.255.0 192.168.1.5 1
netsh interface ip set dns "Local Area Connection" static 192.168.1.200 primary

To change the interface back to using DHCP and so have it allocated a different IP address

netsh interface ip set address "Local Area Connection" dhcp
netsh interface ip set dns "Local Area Connection" dhcp

Emerging Technologies: Developments in Red Hat Enterprise Linux RealTime

by Emerging Technologies Team

You may have heard the news from Red Hat’s CTO Brian Stevens’ keynote at the Red Hat Summit that we are building a realtime variant of Red Hat Enterprise Linux. There were a few sessions at the Summit describing our initiative in more detail. For those of you who weren’t present, we’d like to share some realtime info with you here.

We can simplify the primary functional objectives of our realtime initiative down to a few key points:

1. Determinism: provide consistent, repeatable response times
2. Priority: ensure the highest priority processes run first

Sounds rather basic, right?

For most workloads, a properly tuned Red Hat Enterprise Linux kernel (in RHEL 2.1, 3, 4 or 5) meets customer requirements. Typical timing requirements are in the range of millisecond response time. However for the most demanding customer workloads, the requirements are in the microsecond range. To give just a few representative examples:

* Financial Services industry: here time is money. In this highly competitive market, shaving fractions of a second off the time it takes to performs market analytics yields huge advantage. Additionally, there are increasing government regulations for consistency in trading. They don’t want things smelling fishy if some trades take longer than others.
* Federal command and control systems: here, “close enough” isn’t good enough. They need to dependably know that the highest priority application threads will run and complete in predictable periods of time.

The primary reason why the standard Red Hat Enterprise Linux products can’t completely meet the most demanding response time requirements is because there are numerous lengthy kernel codepaths which are non-preemptable. Without getting too technical here, this means that while these non-preemptable kernel codepaths are running, the high priority application threads are not running. Hence these long-running kernel codepaths result in delays in the application running, which is the cause of inconsistent response times (also referred to as non-determinism). In his keynote address at the Summit, Brian displayed a performance chart illustrating that when running a messaging workload on standard Red Hat Enterprise Linux, there was substantial deviation in response times. Whereas when running the realtime kernel, the response times were highly consistent.

Sun's next goal: A Linux ecosystem

The server and software company launched its servers based on its own UltraSparc T1 "Niagara" chips in December, a major part of a drive to restore its lost lustre and financial strength.

But alongside the hardware launch came a more quiet software push: an attempt to make the Linux and BSD Unix open-source operating systems a serious option for buyers of Sparc-based computers. To promote the technology combination, Sun is trying to coax an accompanying software business into existence.

Sun has had some experience building such software "ecosystems." For example, it's in the process of resurrecting a version of its own Solaris operating system for computers with x86 processors such as Advanced Micro Devices' Opteron. But Sun, which already has several irons in the fire, faces formidable challenges in the Linux and BSD effort.

"The time for Linux on Sparc as any kind of major market phenomenon has come and gone -- over five years ago now, maybe longer," Illuminata analyst Jonathan Eunice said. "It just serves to split the available development resources."

Through projects such as UltraLinux and Aurora Linux, Linux and some BSD variants can already run on Sparc processors. But the products are not commercially relevant for most potential customers. The two major Linux sellers have already pulled back -- Red Hat dropped its Sparc support in 2000, and Novell Suse's last supported version was released in 2002.

Still, Sun has no shortage of gumption. "Linux on Sparc is dead serious," President Jonathan Schwartz said in an e-mail interview. "I'm personally talking to leaders in the community. BSD, too."

The effort is part of Sun's attempt to restore its relevance and financial fortunes by shaking its image as a proprietary technology company. That legacy from the '90s hurt the Santa Clara, California-based company when it missed out on two major growth trends that spanned the rest of the server industry: machines built with x86 processors such as Opteron and Intel's Xeon, and the open-source Linux operating system.

Now, one 180-degree turn later, Sun is making its Solaris an open-source project and plans to do the same with its UltraSparc processor. "To be successful, Solaris has to go beyond Sparc. But also to be successful, Sparc has to go beyond Solaris," said David Yen, who as executive vice president of Sun's Sparc server group is trying to make the chip family "the new industry standard."

Intel to launch Linux-powered mobile Internet device

Intel is developing its own take on the mini-tablet, with a new ultra-mobile PC platform to be announced at this week's Intel Developer Forum in Beijing. The big surprise? It's based on Linux.

Called a Mobile Internet Device (pic), or MID, the devices will have screen sizes from 4.5 to six inches with a target audience described as "consumers and prosumers" rather than mobile professionals.

The MID2007 platform, currently codenamed McCaslin, will gain a more marketing-friendly moniker closer to next year's release of the products. This is tipped to be an extension of the successful Centrino mobile brand, in the same manner as the recent announcement earlier this month of a higher-end Centrino Pro brand for enterprise-class notebooks incorporating Intel's vPro management technology.

While McCaslin's CPU components -- codenamed Stealey -- will be dual-core processors clocked at 600-800MHz and capable of running Windows XP and Vista, Intel plans for the devices to run an embedded Linux OS but with a mix of open-source and proprietary code in the final products.

Typical MID uses will be "staying in touch", entertainment, information and location-based services. Intel's presentation specifically cites Google Maps and Web-based "office and enterprise applications" in the last two categories. Connectivity will be provided through Wi-Fi and support for wide-area coverage via 3G HSDPA.

MID tablets will run a simplified "finger-friendly" user interface optimised for the small screens, based on the Gnome desktop but with an Intel-developed "master user interface" layer to serve as an equivalent to the desktop.

Developers will next month see the first MID-specific OS -- a tweak of China's RedFlag Linux known as RedFlag MIDINUX -- while the IDF schedule itself includes a stream of "ultra mobile sessions" including one on "Designing for Linux-based mobile Internet devices".

Intel first tipped its hand in the UMPC space at least year's IDF, when it showcased several prototype devices no larger than a paperback book and announced a partnership with Yahoo to deliver a rich Web-based back end of business and personal services.

Microsoft HealthVault

Microsoft® HealthVault™ is designed to put you in control of your health information.
A free HealthVault account helps you collect, store and share information with family members
and gives you a choice of applications and devices to help manage your fitness, diet and health.

How HealthVault works

HealthVault isn't just a Web site - it's the hub of a network of Web sites, personal health devices
and other services that you can use to help manage your health.
HealthVault lets you store the information in one central place on the Web.
You're in control of what information you store and can decide who else can see, change, or help manage it.
HealthVault never lets other Web sites or programs see or change the information in your
HealthVault record without explicit permission from you or a record custodian invited to share your records.

Click Here For More Information

Platform As A Service: Cloudo

Platform As A Service: Cloudo


Platform As A Service, or PaaS is the latest development in virtualization. Where companies started to offer applications online (Saas, Software As A Service) and the use of virtual servers is becoming mainstream, more and more companies now offer a complete operating system as a service online.
Cloudo is the latest addition to platform providers. There are several others that have existed for a while now in the consumer market, but to be honest I have no idea if there is a consumer market for this technology. Virtualization is huge in the business market - after offering servers with virtual servers on top even SUN Microsystems now considers offering online platforms for businesses.

So what is so interesting about Cloudo? Why would we want a webbased operating system? Well, something that makes a huge difference is the option to sync your files to the operating system. Until now, nobody else offers this.

There currently is a private beta for developers only, so there's nothing for me there right now. But I will keep an eye on it.

New wireless sensor network keeps tabs on the environment

New wireless sensor network keeps tabs on the environment

Have you ever wondered what happens in the rainforest when no one is looking?.

Research in the University of Alberta's Faculty of Science may soon be able to answer that question. The departments of computing science and earth and atmospheric science have been working together to create a Wireless Sensor Network that allows for the clandestine data collection of environmental factors in remote locations and its monitoring from anywhere in the world where the Internet is available.

The research team, including Pawel Gburzynski, Mario Nascimento, and Arturo Sanchez-Azofeifa, recently launched EcoNet, a functional model of a WSN for environmental monitoring in the display house in the University of Alberta's Agriculture/Forestry Centre. The display house hosts a small but feature-rich environment that mimics that of a tropical forest. Using a WSN, many sensors can continuously monitor factors like temperature and luminosity and will process, store and transmit data co-operatively and wirelessly with other sensors to generate data that can then be collected and made available to users virtually anywhere on the globe. The sensors represent a technology for scientists to monitor diverse phenomena continuously and inconspicuously.

Having the data continuously monitored by scientists substantially increases the chances of uncovering anomalies early enough to investigate them promptly and thoroughly.........

ClearForest Gnosis: The Future of Web Searches

ClearForest Gnosis is early example of the possibilities of semantic web searches,
hinting at the facility semantic web applications will allow in the future.
Gnosis, a plugin for Firefox or Internet Explorer (link currently unavailable),
does a real-time semantic search of textual key words.

Gnosis effectively puts a powerful search engine right into the text of any web page you visit.
After processing the page, Gnosis offers a series of hyperlinks, each one operating like a sort of minisearch,
highlighting people, organizations, medical conditions, companies, currency, city, country, or industry terms,
for example. The thematically color-coded hyperlinks link to automatic searches on Google, Wikipedia,
Facebook, Linked In, Reuters News, Technorati and various financial services.

A simple click on the linked word can either Google it, find it in Wikipedia, or,
if it’s a person, easily find their Facebook or LinkedIn page. Another way Gnosis makes searching
easier is it highlights every instance of a word, instead of just the first time, as is usual on most web sites.

At this point Gnosis mainly serves to make searches faster. It allows you to process a site after you’ve gone to it,
or you can choose to automatically search a site by adding its address to the options menu. Not having to leave the text to type in key words certainly allows for a much quicker gathering of contextual information than a traditional search.

Gnosis is part of Thomson Reuters’ semantic web project, OpenCalais, and is integrated into Reuter’s GIST,
a “360-degree” news service, featuring articles, images, and videos. GIST aims to use ClearForest searches to create its context-based news pages.

Journaled File System Technology for Linux

Journaled File System Technology for Linux

Overview
IBM's journaled file system technology, currently used in IBM enterprise servers, is designed for high-throughput server environments, key to running intranet and other high-performance e-business file servers. IBM is contributing this technology to the Linux open source community with the hope that some or all of it will be useful in bringing the best of journaling capabilities to the Linux operating system.

Developing JFS
JFS is licensed under the GNU General Public License. If there's a feature that you'd like to see added to JFS, consider becoming a part of the JFS development process. Since JFS is an open source project, it's easy to get involved.

Click Here For More Information

Microsoft Surface:New Technology From Microsoft.

Microsoft Surface (Codename: Milan), is a Multi-touch product from Microsoft which is developed as a
software and hardware combination technology
that allows a user, or multiple users, to manipulate digital content by the use of natural motions,
hand gestures, or physical objects. It was announced on May 29, 2007 at D5 conference.
Initial customers will be in the hospitality businesses, such as restaurants, hotels, retail,
public entertainment venues and the military for tactical overviews.
The preliminary launch was on April 17, 2008, when Surface became available for customer use in AT&T stores.

Overview-
Surface is essentially a Windows Vista PC tucked inside a table, topped with a 30-inch reflective surface
in a clear acrylic frame. A projector underneath the surface projects an image onto its underside,
while five cameras in the machine's housing record reflections of infrared light from human fingertips.
The camera can also recognize objects placed on the surface if those objects have specially-designed "tags"
applied to them. Users can interact with the machine by touching or dragging their fingertips and objects
such as paintbrushes across the screen, or by placing and moving tagged objects.

Surface has been optimized to respond to 52 touches at a time. During a demonstration with a reporter,
Mark Bolger, the Surface Computing group's marketing director, "dipped" his finger in an on-screen paint palette,
then dragged it across the screen to draw a smiley face. Then he used all 10 fingers at once to give the face
a full head of hair.

Using the specially-designed "tags" on objects, Microsoft Surface can automatically offer
additional wine choices tailored to the dinner being eaten based on the type of wine set on the Surface.

Click on following link--
See The Video

Zimbra:-messaging and collaboration

Zimbra™ Collaboration Suite is a full-featured messaging and collaboration
solution that includes email, address book, calendaring, tasks, and Web
document authoring.

The Zimbra Collaboration Suite is designed to provide an end-to-end mail
solution that is scalable and highly reliable. The messaging architecture is built
with well-known open-system technology and standards and is composed of a
mail server application and a client interface.

The architecture includes the following core advantages:

• Open source integrations. Linux®, Jetty, Postfix, MySQL®, OpenLDAP®.
• Uses industry standard open protocols. SMTP, LMTP, SOAP, XML,
IMAP, POP.
• Modern technology design. Java, JavaScript thin client, DHTML.
• Horizontal scalability. Because each mailbox server includes its own data
store, message store, and set mailbox accounts, you don’t change
anything on existing servers in order to scale the system. To scale for
additional mail accounts, add more servers.
• Browser based client interface. Zimbra Web Client gives users easy
access to all the ZCS features
• Administration console to manage accounts and servers.

Core Functionality

The Zimbra Collaboration Suite is an innovative messaging and collaboration
application that offers the following state-of-the-art messaging and
collaboration solutions:
• Email
• Group Calendars
• Address Books
• Task Management
• Web document management and authoring.

RAID Level in Details

What is RAID?

RAID allows information to access several disks. RAID uses techniques such as disk striping (RAID Level 0), disk mirroring (RAID Level 1), and disk striping with parity (RAID Level 5) to achieve redundancy, lower latency, increased bandwidth, and maximized ability to recover from hard disk crashes.

RAID consistently distributes data across each drive in the array. RAID then breaks down the data into consistently-sized chunks (commonly 32K or 64k, although other values are acceptable). Each chunk is then written to a hard drive in the RAID array according to the RAID level employed. When the data is read, the process is reversed, giving the illusion that the multiple drives in the array are actually one large drive.

Hardware RAID

The hardware-based array manages the RAID subsystem independently from the host. It presents a single disk per RAID array to the host.

A Hardware RAID device connects to the SCSI controller and presents the RAID arrays as a single SCSI drive. An external RAID system moves all RAID handling "intelligence" into a controller located in the external disk subsystem. The whole subsystem is connected to the host via a normal SCSI controller and appears to the host as a single disk.

RAID controller cards function like a SCSI controller to the operating system, and handle all the actual drive communications. The user plugs the drives into the RAID controller (just like a normal SCSI controller) and then adds them to the RAID controllers configuration, and the operating system won't know the difference.

Software RAID

Software RAID implements the various RAID levels in the kernel disk (block device) code. It offers the cheapest possible solution, as expensive disk controller cards or hot-swap chassis [1] are not required. Software RAID also works with cheaper IDE disks as well as SCSI disks. With today's faster CPUs, Software RAID outperforms Hardware RAID.

The Linux kernel contains an MD driver that allows the RAID solution to be completely hardware independent. The performance of a software-based array depends on the server CPU performance and load.

To learn more about Software RAID, here are the key features:

*

Threaded rebuild process
*

Kernel-based configuration
*

Portability of arrays between Linux machines without reconstruction
*

Backgrounded array reconstruction using idle system resources
*

Hot-swappable drive support
*

Automatic CPU detection to take advantage of certain CPU optimizations


RAID Levels and Linear Support

RAID supports various configurations, including levels 0, 1, 4, 5, and linear. These RAID types are defined as follows:

*

Level 0 — RAID level 0, often called "striping," is a performance-oriented striped data mapping technique. This means the data being written to the array is broken down into strips and written across the member disks of the array, allowing high I/O performance at low inherent cost but provides no redundancy. The storage capacity of a level 0 array is equal to the total capacity of the member disks in a Hardware RAID or the total capacity of member partitions in a Software RAID.
*

Level 1 — RAID level 1, or "mirroring," has been used longer than any other form of RAID. Level 1 provides redundancy by writing identical data to each member disk of the array, leaving a "mirrored" copy on each disk. Mirroring remains popular due to its simplicity and high level of data availability. Level 1 operates with two or more disks that may use parallel access for high data-transfer rates when reading but more commonly operate independently to provide high I/O transaction rates. Level 1 provides very good data reliability and improves performance for read-intensive applications but at a relatively high cost. [2] The storage capacity of the level 1 array is equal to the capacity of one of the mirrored hard disks in a Hardware RAID or one of the mirrored partitions in a Software RAID.
*

Level 4 — Level 4 uses parity [3] concentrated on a single disk drive to protect data. It is better suited to transaction I/O rather than large file transfers. Because the dedicated parity disk represents an inherent bottleneck, level 4 is seldom used without accompanying technologies such as write-back caching. Although RAID level 4 is an option in some RAID partitioning schemes, it is not an option allowed in Red Hat Enterprise Linux RAID installations. [4] The storage capacity of Hardware RAID level 4 is equal to the capacity of member disks, minus the capacity of one member disk. The storage capacity of Software RAID level 4 is equal to the capacity of the member partitions, minus the size of one of the partitions if they are of equal size.
*

Level 5 — This is the most common type of RAID. By distributing parity across some or all of an array's member disk drives, RAID level 5 eliminates the write bottleneck inherent in level 4. The only performance bottleneck is the parity calculation process. With modern CPUs and Software RAID, that usually is not a very big problem. As with level 4, the result is asymmetrical performance, with reads substantially outperforming writes. Level 5 is often used with write-back caching to reduce the asymmetry. The storage capacity of Hardware RAID level 5 is equal to the capacity of member disks, minus the capacity of one member disk. The storage capacity of Software RAID level 5 is equal to the capacity of the member partitions, minus the size of one of the partitions if they are of equal size.
*

Linear RAID — Linear RAID is a simple grouping of drives to create a larger virtual drive. In linear RAID, the chunks are allocated sequentially from one member drive, going to the next drive only when the first is completely filled. This grouping provides no performance benefit, as it is unlikely that any I/O operations will be split between member drives. Linear RAID also offers no redundancy and, in fact, decreases reliability — if any one member drive fails, the entire array cannot be used. The capacity is the total of all member disks.

Linux File System Structure.

Overview of File System Hierarchy Standard (FHS)

Red Hat Enterprise Linux uses the Filesystem Hierarchy Standard (FHS) file system structure, which defines the names, locations, and permissions for many file types and directories.

The FHS document is the authoritative reference to any FHS-compliant file system, but the standard leaves many areas undefined or extensible. This section is an overview of the standard and a description of the parts of the file system not covered by the standard.

Compliance with the standard means many things, but the two most important are compatibility with other compliant systems and the ability to mount a /usr/ partition as read-only. This second point is important because the directory contains common executables and should not be changed by users. Also, since the /usr/ directory is mounted as read-only, it can be mounted from the CD-ROM or from another machine via a read-only NFS mount.

FHS Organization

1) The /boot/ Directory

The /boot/ directory contains static files required to boot the system, such as the Linux kernel. These files are essential for the system to boot properly.

2)The /dev/ Directory

The /dev/ directory contains device nodes that either represent devices that are attached to the system or virtual devices that are provided by the kernel. These device nodes are essential for the system to function properly. The udev demon takes care of creating and removing all these device nodes in /dev/.

Devices in the /dev directory and subdirectories are either character (providing only a serial stream of input/output) or block (accessible randomly). Character devices include mouse, keyboard, modem while block devices include hard disk, floppy drive etc. If you have GNOME or KDE installed in your system, devices such as external drives or cds are automatically detected when connected (e.g via usb) or inserted (e.g via CD or DVD drive) and a popup window displaying the contents is automatically displayed. Files in the /dev directory are essential for the system to function properly. Examples of common files in the /dev include:

/dev/hda - the master device on primary IDE channel.
/dev/hdb - the slave device on primary IDE channel.
/dev/tty0 - first virtual console.
/dev/tty1 - second virtual console.
/dev/sda - first device on primary SCSI or SATA channel.
/dev/lp0 - first parallel port.

3)The /etc/ Directory

The /etc/ directory is reserved for configuration files that are local to the machine. No binaries are to be placed in /etc/. Any binaries that were once located in /etc/ should be placed into /sbin/ or /bin/.

Examples of directories in /etc are the X11/ and skel/:


/etc
|- X11/
|- skel/

The /etc/X11/ directory is for X Window System configuration files, such as xorg.conf. The /etc/skel/ directory is for "skeleton" user files, which are used to populate a home directory when a user is first created. Applications also store their configuration files in this directory and may reference them when they are executed.

4) The /lib/ Directory

The /lib/ directory should contain only those libraries needed to execute the binaries in /bin/ and /sbin/. These shared library images are particularly important for booting the system and executing commands within the root file system.

5)The /media/ Directory

The /media/ directory contains subdirectories used as mount points for removeable media such as usb storage media, DVDs, CD-ROMs, and Zip disks.

6)The /mnt/ Directory

The /mnt/ directory is reserved for temporarily mounted file systems, such as NFS file system mounts. For all removeable media, please use the /media/ directory. Automatically detected removeable media will be mounted in the /media directory.

7)The /opt/ Directory

The /opt/ directory provides storage for most application software packages.

A package placing files in the /opt/ directory creates a directory bearing the same name as the package. This directory, in turn, holds files that otherwise would be scattered throughout the file system, giving the system administrator an easy way to determine the role of each file within a particular package.

For example, if sample is the name of a particular software package located within the /opt/ directory, then all of its files are placed in directories inside the /opt/sample/ directory, such as /opt/sample/bin/ for binaries and /opt/sample/man/ for manual pages.

Packages that encompass many different sub-packages, data files, extra fonts, clipart etc are also located in the /opt/ directory, giving that large package a way to organize itself. In this way, our sample package may have different tools that each go in their own sub-directories, such as /opt/sample/tool1/ and /opt/sample/tool2/, each of which can have their own bin/, man/, and other similar directories.

8)The /proc/ Directory

The /proc/ directory contains special files that either extract information from or send information to the kernel. Examples include system memory, cpu information, hardware configuration etc.

Due to the great variety of data available within /proc/ and the many ways this directory can be used to communicate with the kernel, an entire chapter has been devoted to the subject. For more information, refer to Chapter 3, The proc File System.

9)The /sbin/ Directory

The /sbin/ directory stores executables used by the root user. The executables in /sbin/ are used at boot time, for system administration and to perform system recovery operations. Of this directory, the FHS says:

/sbin contains binaries essential for booting, restoring, recovering, and/or repairing the system in addition to the binaries in /bin. Programs executed after /usr/ is known to be mounted (when there are no problems) are generally placed into /usr/sbin. Locally-installed system administration programs should be placed into /usr/local/sbin.

At a minimum, the following programs should be in /sbin/:


arp, clock,
halt, init,
fsck.*, grub,
ifconfig, mingetty,
mkfs.*, mkswap,
reboot, route,
shutdown, swapoff,
swapon

Network Monitoring-Nagios

What Is This?

Nagios® is a system and network monitoring application. It watches hosts and services that you specify,
alerting you when things go bad and when they get better.
Nagios was originally designed to run under Linux, although it should work under most other unices as
well.

Some of the many features of Nagios include:

Monitoring of network services (SMTP, POP3, HTTP, NNTP, PING, etc.)
Monitoring of host resources (processor load, disk usage, etc.)
Simple plugin design that allows users to easily develop their own service checks
Parallelized service checks
Ability to define network host hierarchy using "parent" hosts, allowing detection of and distinction
between hosts that are down and those that are unreachable
Contact notifications when service or host problems occur and get resolved (via email, pager, or
user-defined method)
Ability to define event handlers to be run during service or host events for proactive problem
resolution
Automatic log file rotation
Support for implementing redundant monitoring hosts
Optional web interface for viewing current network status, notification and problem history, log
file, etc.

Real world Ruby

I am working on Ruby language since last few months. I really wondered, this is so beautyful language to work with, so what could be various usages of this great language? I Googled a bit for this and found many fascinating facts. I thought like sharing this information with you. Many people use Ruby in their daily jobs, others as hobby. But there are many other useful and important areas where Ruby is being used.

Simulations
NASA Langley Research Center uses Ruby to conduct simulations.

A research group in Motorola uses Ruby to script a simulator, to generate scenarios as well as to post process the data.

3D Modelling
Google SketchUp is a 3D modelling application which uses Ruby for its macro scripting API.

Business
Toranto Rehab uses a RubyWebDialogs based application to manage and track on-call and on-site support for IT help desk and IT operations teams.

Robotics
At MORPHA project, Ruby was used to implement reactive control part for the Siemens service robot.

Networking
Open Domain Server uses Ruby to allow people using dynamic DNS clients to update their IP configuration in real time so that it can be mapped to static domains.

Telephony
Ruby is being used within Lucent on a 3G wireless telephony product.

System Administration
Ruby was used to write the central data collection portion of Level 3 communications Unix capacity and planning system that gathers performance statistics from over 1700 Unix (Solaris and Linux) servers scattered around the globe.

Web Applications
Basecamp, a web-based project management application developed by 37signals is programmed entirely in Ruby.

43 things allows you to keep a list of goals and share it with the world. It was developed entirely in Ruby.

A List Apart, a magazine for people who make websites that has been around since 1997, has recently been revamped and uses a custom application built with Ruby on Rails.

Blue Sequence, a sophisticated mission-critical application which forms part of Toyota Motor Manufacturing's own "Sequence-in-time" production process, has recently been selected as finalist in this years British Computers (BCS) Information Management Awards.