Cover Story: Linux in the enterprise
Linux in enterprises - A brief look

Here’s how public and private sector companies are using Linux for mission critical applications world-wide. by Minu Sirsalewala

An assured platform
New India Assurance Company Limited (NIA) is one of the oldest and largest non-life insurance companies in India. The company has around 200 products across verticals that range from insurance of bullock-carts to insurance of satellites. It has 26 regional offices, 397 divisional offices, 649 branches, and 39 direct agent branches. It also has operations in 23 other countries.

NIA used to run a mix of Openserver 5 and UnixWare 7 in 1,192 servers across the country and had purchased enterprise licenses for them. The standard server configuration was Pentium III, one CPU, and 1 GB RAM. But the enterprise servers experienced several crashes over time. The company needed a more stable and reliable system to run its business applications smoothly and without failure points.

Linux on the servers
The company decided to migrate to Red Hat Linux. It has been using Red Hat 7.1 and 7.3 for the last 15 months and Red Hat Linux Advanced Server since July 2002. The Linux-based servers are used to run applications like Oracle 9i, mail and messaging, Firewall, DNS, Internet, Intranet, e-mail, and LDAP. The Web-based Intranet is used by 500 employees.

Why Linux
The company chose Linux to avoid licensing hassles. It also felt that the OS will provide easy installation, configuration, and administration. Basant Kerketta, System Analyst, NIA, explained, "Since we experienced several crashes we looked for an alternative. When we heard of Linux, we installed Linux on a few servers, deployed Oracle and a few business applications on them. The servers ran very smoothly. We could generate and print reports much faster."

Security
The company felt that Linux is more secure than other OSs because there are minimal open ports. The company's Firewall runs on a Linux-based server.

Scalability
NIA implemented Linux on two servers for e-mail and added more hardware over a period of time. The severs performed optimally and were able to handle load balancing and fail-over across the systems.

Manageability
"Most Linux functions can be installed and forgotten," said Basant. "The task of an administrator is simplified and there is no need to keep constant vigil." The servers are managed remotely with Secure Shell (SSH) and a Web interface."

Price/performance
Basant said, "We feel guilty for not being able to match our price for its performance. If we compare the present scenario with our past experience of implementing and maintaining other OSs, Red Hat Linux Advanced Server performs far better than these, and it costs less than five percent of other OSs."

The company plans to migrate the entire Unix-based platforms to Red Hat Linux Advanced Server by the end of this year.

Rolta on Linux
Rolta India Limited (RIL) provides engineering solutions and IT services to customers globally. It also offers ISP services in Mumbai, its global headquarters. In the competitive ISP space, the company felt it necessary to reduce the cost-per-subscriber. The solution was to cut down expenditure on exorbitant licensing and AMC fees by deploying open source software as a platform to offer Internet services.

Some Linux
The company deployed Red Hat 6.2 on the database, e-mail, LDAP, and bandwidth manager servers. These servers have dual or four-way CPUs on Xeon and Pentium II/III; and uses 512 MB to 1 GB RAM.

Why Linux?
RIL felt that Linux has an advantage over other OSs because of its open source nature. The user has the flexibility to modify the source code as per requirements and can customize it to specific business needs. The cost of procurement is very low. And with the level vendor support currently offered, there is a high amount of expertise available in the market.

Security
The security and access control features have been developed by the in-house team, who has a lot of technical expertise in Linux.

Scalability
Vinay Sawarkar, Executive Director, eServices, Rolta said, "We continuously upgrade our infrastructure for the ISP services. We use a load-balancing solution where we can deploy multiple servers/processors when required. The OS supports these changes without any technical problems."

Manageability
The company has developed its own network management solution which monitors services and other hardware processes and sends out alerts to administrators 24x7, through e-mail and SMS. "The performance is stable and the servers running Linux do not need to be rebooted for years," explained Sawarkar.

The company has also built an eCompetency center where it showcases Linux-based eSecurity products. This eCompetency center is a Proof of Concept lab where prospective clients can view a simulation of the product's functionalities.

Google's OS search
Google (www.google.com) needs no introduction. One of the most widely used search engines, Google is fast, accurate and easy to use.

Google needed a powerful solution to run its cluster of 8,000 computers over 10,000 nodes, in a cost-effective way. The site records millions of hits every day and thus needs an OS that can withstand the load. The solution also had to be powerful enough to provide in-depth searching capabilities.

Linux steps in
The company decided to go in for Linux and now operates its search engines and computing functions on a cluster of approximately 8,000 Red Hat Linux servers. All the Google servers are unbranded PCs that include an array of Intel CPUs—400 MHz to 533 MHz Celeron processors, and 400 MHz to 466 MHz Pentium II processors. Each server has at least 256 MB of memory, with some going up to 1 GB. The cluster of Red Hat servers is composed of several sub-clusters, each comprising 200 to 300 servers.

Why Linux?
Google.com chose Red Hat over other Unix/Linux distributions not only because of the cost saving on license fees, but also because the OS stood out as a mature distribution with a package comparable to commercial Unix flavors.
Also, among the other low-cost Linux distributions like Debian and Slackware, Red Hat Linux stood out as a more mature distribution.

Scalability
Google is running one of the largest Linux clusters in the world—over 8,000 systems and growing. Using off-the-shelf, unbranded Intel-powered hardware coupled with the Red Hat Linux operating system, Google achieved the highest possible density at the lowest possible cost.

Manageability
The main attraction of Red Hat Linux for Google has been the ability to maintain thousands of low-cost, redundant servers with freely available tools like shell, Perl, and Python scripts. The built-in flexibility of an open source platform lent itself to the development of more complicated search functions.

Linux on Mainframe at ER&DCI
The Electronics Research and Development Centre of India (ER&DCI), Thiruvananthapuram, is an autonomous scientific society of the Ministry of Communications and Information Technology, Government of India, which develops electronic and IT applications. Their clientele includes national and international organizations from the government and corporate sectors.

The company wanted to offer applications-based services to various government departments as an ASP. This would involve hosting various applications and databases on individual servers in a farm.

The company used Linux as the OS platform along with z/VM in different logical partitions and deployed IBM DB2 Universal Database and Websphere Application server to provide the desired application services. The hardware used was IBM's zSeries Multiprise 3000 model 7060-H50. The company also used Intel-based servers running Linux.

Why Linux?
ER&DCI chose to use Linux because it saved the cost of procuring an OS, and the source code is under constant scrutiny by the open source community. The company did not feel restricted to a specific vendor and was pleased that many ISVs were developing applications for Linux. The company also found it easy to port applications to Linux. Linux offered ER&DCI different levels of security and flexibility.

System
The system shares the memory and disk storage between three logical partitions (LPAR). Each LPAR runs native OSs. Linux and z/VM have been implemented as native OSs. Under z/VM, several Linux OSs can work as guests, presenting an environment of multiple OSs sharing the processor, memory, and storage. Each Linux guest is equivalent to a server, which may be configured as an application server, Web server, or database server of very high computing capability. The hardware has internal security features, which add to OS security.

Security
Traditional Linux security mechanisms like user authentication and password protection can be utilized. Native file-system level and file access privileges can be limited to authorized administrators from specific consoles. Single sign-on authentication can be extended to the applications hosted on the OS. Session level security is enabled using Secure Shell (SSH).

Scalability
The machine currently uses IBM's 7060-H50 processor. It uses one CPU and 2 GB memory. This machine can be upgraded to a 7060-H70 which uses two CPUs and 4 GB memory. In this case the Linux OS does not need to be replaced.

Manageability
ER&DCI claims that it's easier to manage the systems compared to a distributed system.

Vendor support
IBM offers strong support for the Linux applications, which run on its hardware.

C-DAC’s HPC initiative
The Center for Development of Advanced Computing (C-DAC) makes supercomputers that are used for heavy-duty data processing in jobs like oil exploration and weather forecasting. The company needed reliable and stable software for its high-performance computing lab in Bangalore. So it decided to deploy Linux to fulfil its needs.
C-DAC now runs a number of Linux-based applications like e-governance solutions, network proxy/security, office automation, embedded systems, Indian language products, and high-performance computing functions. The company also uses language script tools on the OS.

Why Linux?
R.K. Arora, Executive Director, C-DAC says, "High-performance computing has traditionally been a domain of interest for the scientific and engineering community. Consequently, high-performance computing initiatives using Linux has been in vogue. Keeping with the times C-DAC has adopted Linux for its high-performance computing lab at Bangalore."

Security
The company feels that Linux performs well on the security front. There is a large community working on the Linux code. Since the open source code is open to review and test by an equally large number of users, coding errors and vulnerabilities are discovered and corrected very rapidly. For similar reasons the open source programs can be scrutinized for security flaws on a regular basis.

Performance
C-DAC feels that Linux is very flexible and adaptable. And these characteristics lend itself to implementation in a variety of IT architectures. Linux allows the company to speed integration and implementation of new applications across its heterogeneous environments.

Price/performance
The use of Linux has resulted in low TCO for the company due to aspects like reduced or no licensing fees, ability to run on lower cost hardware, less expensive upgrades, and easily available technical pool.

Vendor support
Open source software is not owned or controlled by any one developer or vendor. Hence organizations retain the choice of deciding on support and development partners, from a large pool of in-house as well as external resources.

Amazon hunts for an OS
Amazon (www.Amazon.com) is one of the largest online retailers of books, toys, music, DVDs, electronics, houseware, and a variety of other products. It has one of the largest data warehouses in the world which is a central point for all its data—including order data, customer data, and inventory data—that supports
user analysis.

The online nature of its business needs 24x7 availability of data, and no single point of failure. The online retailer was looking for new ways to reduce operating costs—without affecting the positive customer experience associated with running the user-friendly site. It decided to use Linux as a server platform to save license costs.

The Linux prize catch
The company has deployed HP Superdome servers with the Linux-based operating environment across its entire global enterprise. The Oracle database and the front-end of its data warehouse runs on these servers. The front-end of Amazon.com's data warehouse is a collection of HP LT6000 Intel-based Linux servers. The Linux systems support the company's extract, transform, load processing functions, and supports the user interface. The hardware is in the form of thin, rack-mountable models with Intel processors and Red Hat Linux as the OS.

Why Linux?
Amazon.com's key business strategy was to lower operating costs and pass the benefits to its customers in the form of lower prices. It found that the overall cost of ownership including the hardware, software, staffing, and purchasing & retirement costs are significantly less compared to other OSs.

The company felt that the OS could be downloaded free, or a single copy bought from a company like Red Hat or SuSE. The OS can then be installed on any number of computers. It comes bundled with other software for sending Web pages to the user’s browser or running company e-mail.

The company does not have to pay extra licensing fees for the computers that connect to Linux servers. Linux's open-source licensing policy makes it simpler for the company to make sure its computers are in compliance with license restrictions. This is a benefit over other OSs' per-seat licensing plans that can result in costly and legally daunting audits.

Manageability
The company feels that Linux involves less administrative costs and chances of the system crashing are negligible. There is no need to reboot the system.

Vendor support
HP helped Amazon migrate its customized software on the earlier Unix servers from Sun Microsystems to the Linux servers.