Cover Story: Linux in the enterprise
Painting a coat of Linux

Till 1997 Asian Paints India Limited used proprietary OSs in its network. Linux was first introduced on the company's mail servers. Impressed by its performance and cost benefits, the company has deployed it on its mission critical servers. by Soutiman Das Gupta

Asian Paints India Limited (APIL) is India's largest paint company with a turnover of Rs 16.56 billion (USD 340 million). It is present in 94 locations nationwide and runs critical enterprise applications like SAP R/3, SAP Business Information Warehouse, mySAP CRM, and a range of solutions from i2 on its servers.

In 1997, APIL first deployed Linux on its mail servers. Impressed with its features and performance, the company gradually migrated many of its mission critical applications to Linux as well. It now runs 45 Linux servers using a combination of Red Hat 6.0 and SuSE 7.x distributions. Linux servers comprise almost 20 percent of the server infrastructure. Besides the usual mail and messaging applications, these servers are used to run ERP modules and B2B applications, an area where zero downtime is a key necessity.

The company deployed Linux servers and applications in a phased manner. It first used Linux for non-mission critical applications like intranet and messaging. Once convinced about the stability and cost benefits, the next step was to migrate mission critical applications to Linux.

1997 - The initiation
In 1997 the company had around 75 NetWare- and NT-based servers in its network. All the branch office servers used NetWare. It purchased MS Exchange to centralize e-mail management functions and ran it for around six months. But the company felt that the application was very bandwidth-intensive. The nationwide branch offices were linked through VSAT since leased lines were not easily available at that time, and VSAT bandwidth is expensive.

Microsoft also had a client-based licensing policy. P. Rambabu, General Manager-IT, APIL said, "We had to buy an NT user license along with the Exchange license to access mail. In effect, we had to purchase a dual license and the total cost per user worked out to be around Rs 5,000." In the meantime, the IS Team at APIL had dabbled with Linux and gathered a significant amount of technical documentation on the OS. It concluded that a shift to Linux will save cost on license fees, consume less bandwidth, and save cost on hardware since the OS can even function on a simple PC rather than a server.

The NT-based servers were replaced with seven 486 DX PCs with 66 MHz processors. The Intranet server was also migrated to Linux. The qmail application and OpenLDAP directory services were deployed, and management policies were set on the servers.

"It was a quick rollout. Our staff did not need any training as in the case of MS Exchange. The setup performed wonderfully well and we decided to use more applications on Linux as we had found a foothold into the technology," said Rambabu. "And the presence of distribution vendors like Red Hat and SuSE in India addressed the technical support issues."

Linux grows
What started as a controlled experiment developed into an exciting technology avenue. APIL began to develop HTML-, Java-, and PHP-based applications and was able to relate them to the database.

But qmail on Linux did not perform efficiently on the bandwidth utilization front. Since Linux is an open source OS, the IS team at APIL tweaked the source code to achieve the desired result. Later on, the company migrated from qmail to Postfix, an open source product from IBM. Intranet development and testing functions were also performed on Linux. The company then decided to procure an ERP to organize its transaction processing procedures.

SAP on Linux
"SAP had begun to support the use of Linux around two years ago. This gave us the confidence to use a Linux-based server platform for the SAP ERP modules," said Rambabu.

In early 2001 APIL implemented SAP on three HP-UX servers. The server platforms were slowly migrated to Linux and new Linux-based servers were introduced. The company now has seven application servers that run the critical ERP modules. Five of the seven servers are Linux-based and handle the bulk of the processing load. The servers support 500 concurrent users nationwide. SAP development and testing processes are performed on Linux-based servers to save costs on licenses. Rambabu was happy with the decision to use Linux-based servers and said, "The Linux servers give us a very robust price/performance benefit."

Since APIL was planning to run commercial applications like databases and ERP modules, it had to go in for a commercial distribution of Linux. "We could not simply download kernels from the Web or use those offered free in magazines. We had to use specific kernels," explained Rambabu. The company invested in SuSE Linux Enterprise Server since this distribution is optimized for mission critical, high-availability and high-performance computing.
"And the hardware really performs well in this case. Enterprise editions of Linux distributions like SuSE now include Symmetric Multiprocessing (SMP) systems by default. So we loaded these particular distributions and the servers were able to perform load balancing and distribution functions," said Rambabu. The SAP applications run on servers with Xeon CPUs and 4 GB RAM.

Other apps on Linux
APIL runs i2's Demand, Factory, and Supply Chain Planner for factory scheduling. The supply chain operations require order input into SAP modules and then subsequently into i2 for scheduling. The company has deployed an integration platform from webMethods to serve as a common backbone to connect these systems and exchange information about scheduling and ordering processes across SAP, i2 and other systems. This critical middleware solution runs on Linux. HP OpenView is used to manage the network which runs with the help of a Linux agent.

Managing security issues
APIL's security infrastructure comprising of VPN, Firewalls, and access control mechanisms like RADIUS (Remote Authentication Dial-In User Service), used to run on Linux.

"We evaluated FreeBSD and found it provided more rugged security features and is a better technology for hardening systems. FreeBSD offers a very small footprint, which helps a server perform its functions very effectively," said Rambabu. So the company migrated these applications to a FreeBSD platform and now has around five FreeBSD servers.

Performance & cost
APIL feels that the teething problems for Linux are the same as that of any other OS. It is essential to have technical personnel trained in the use of Linux since a number of management features are not available through the GUI. One has to use the Command Line Interface (CLI) to perform management functions, tuning, and tweaking. The OS does not show unpredictable performance in a properly configured system. The company has signed AMCs with Red Hat and SuSE, which include patches and kernel releases.

In terms of costs, the only investment the company has made is in purchasing the SuSE enterprise kernels. The total cost over time has been around Rs 2 lakh. This does not include cost of manpower and customization.
"The incremental cost is less compared to proprietary OSs, which need agents and other software to be used in conjunction," explained Rambabu. "The decision to use Linux is a matter of organizational comfort. Linux is still not an accepted corporate technology in many enterprises. People still think it to be in the realm of geeks. So a huge amount of organizational backing is required."

Soutiman Das Gupta can be reached at soutimand@networkmagazineindia.com