Tackling a data explosion

Faced with the problem of managing exploding data storage requirements, Texas Instruments India chose to implement a combination of DAS and NAS. by Prashant L. Rao

Texas Instruments (TI) was the first MNC to set up R&D operations in India's Silicon Valley. Over the years, the company's Bangalore setup has grown to become a major design center. Along with its growing success in creating chips for a global audience, TI India's data requirements have grown apace.

N.V. Kameswar, General Manager, Information Technology, Texas Instruments India says, "The way storage has grown is commensurate with the growth of design projects at TI India. Not only has the number of projects gone up, the complexity of projects has increased significantly. People who used to ask for gigabytes are now asking for terabytes."

In December 2000, TI had 3 TB of storage. By the end of 2001 that had gone up to 9 TB, and by the end of this year it is expected to be 17 TB. Personal data in the form of e-mail, home directory files etc account for less than 1 TB. The bulk of TI's data consists of design project files.

TI India uses a mix of Solaris and Linux servers; the server pool consists of 900 CPUs. The server protocol used is NFS and NIS is used for providing IPs and to reference data areas. As a result, TI looked for CIFS and NFS support. Another critical requirement was the ability to take snapshots.

Why NAS?
As a design center with high-end computing requirements, TI India needed to store its compute farm data. NAS was a logical choice as most of TI's data is file data.

"A SAN will not work because we don't read data off a disk array, it's all Unix file data," says Tony Idiculla, Lead Engineer, DCE & IT, Texas Instruments India.

The next step was to choose a vendor and TI chose NetApp.

"The global strategy team recommended NetApp filers as part of global standardisation. The aim was to have a common operating environment and avoid reinventing the wheel," says Kameswar. "People design chips and we help them. To make that happen we need global standards."

Standardisation helps transfer data between TI's many design sites.

Today, TI India hosts its data in a mix of NAS (NFS+CIFS) and DAS (FC-AL based) devices. However, its predominant platform is NAS, hosted out of Network Appliance filers.

Implementation
The company did a pilot that lasted between two and three months. F760 filers were used for the evaluation (an old generation box from NetApp). The pilot deployment consisted of 3 TB across two of these filers.

The actual deployment took ten days. Six F840s were installed at TI. Today, TI Bangalore has deployed six F840s and four F880s. The first rollout was done by teams from TI and NetApp. Wipro Infotech was selected to handle the AMC and facilities management. The company has purchased 47 TB of raw capacity across 10 filers in five clusters. Of this, 35 TB is the usable space with the remainder being used for creating file systems, creating a RAID 4 system. TI is using a RAID group size of eight, which is the standard recommended by Network Appliance.

Functions
This implementation has given TI India a common storage pool where any server can access data stored on any filer. That said, the bulk of TI's data is project-based and stored in specific locations. There is an 'application pool' that most of the chip designers access. This application pool is handled by a filer or a set of filers. In each filer the data is pumped through the head. Disk arrays are attached to the NAS head. There are two filers in a cluster supplying data using NFS (Solaris) or CIFS (Windows). If one NAS head fails the other takes over, providing data from both filers. The redundancy exists only from the processor perspective, data is still readable if a processor fails. This failover works down to the Ethernet MAC address.

"You can scale up by adding disks, this is the advantage of using RAID 4," says Idiculla. Today TI uses a mix of F840s and F880s. The F840 was introduced in December 2000. The F880s were launched in 2001 and TI procured them as well. The F880s have superior capacity and better processors in addition to which they support dual processors. The 880s also have newer firmware and scalability is higher in a cluster environment. The F880 offers a maximum raw capacity of 16 TB. NetApp's Data ONTAP software can scale up to this level.

Benefits
After implementing NetApp's storage solution, TI appreciates the following benefits:

• Interoperability: NetApp's filers work with PCs and Unix servers.
• Snapshots: Using this feature, user home directories are backed up each night (recycled).
• NDMP (Network Data Management Protocol) 'serverless' backup: Using Veritas backup software taking advantage of NDMP lets TI backup without affecting server load.
• Block level transfer from filer to tape: The NetApp filer can transfer data in block mode to tape (Fuji).
• Scale up on the fly: Both disks and shelves of disks can be hot-plugged. The older FC9 racks have seven drives and two power supplies. The newer racks support 14 discs and two power supplies.

Future
Looking forward, TI India would like to focus on scalability and disaster recovery (DR). "We are currently adding approximately 1 Terabyte of storage every month," says Kameswar. So TI will have to keep adding disks, racks and filers as demand increases. Over and above that, there's the issue of disaster recovery. Today there is no disaster recovery site. However, TI does have offsite storage of backup tapes. A DR solution is a high priority activity for TI India this year.

Prashant L. Rao can be reached at prashant@expresscomputeronline.com