Storage automation: the future of Serial ATA, tape, CIM, and IP connectivity - Storage Networking - Industry Overview

Computer Technology Review, Oct, 2002

The editors of CTR were curious about what the industry had to say about the impact of Serial ATA, tape, CIM, and IP connectivity on storage automation solutions. So we asked companies to cast an eye toward the foreseeable future. Read on to see what they envisioned.

Will Serial ATA impact disk-automation solutions for disk-to-disk (D2D) backup? When? How?

Mike Wentz, Senior Director of Customer Engineering, 3ware

Disk-to-disk (D2D) is basically backing up expensive disks to cheap disks. It's typically used as a tape replacement.

Serial ATA will help:

(1) Legitimize ATA as a storage target.

(2) Scale to much larger capacities than parallel ATA.

(3) Is capable of higher bandwidth (planned upgrades to 300MB/sec and 600MB/sec over the next few years).

Bottom line: SATA should accelerate D2D.

The major driving factor of D2D backup is the price per MB and the performance of ATA drives when utilizing 32KB block transfers, not necessarily the ATA vs. SATA interface. The major advantage of SATA in this environment will be just the ease of cabling and the extended distances of those cables.

All of the companies that are creating these type of solutions today, that are using ATA, are expected to transition to SATA by mid next year. The only thing that may slow that up is the expected $10 to $20 dollar cost delta between like capacity ATA drives. This delta is expected to decline quickly and disappear over the next 18 months. Some of the larger companies involved in this space (EMC, NetApp) are converting from another interface to ATA to provide the scaling capacity that they require. In these cases, the cost difference will be transparent because 12-port SATA products like 3ware's will allow them to eliminate the SCSI to ATA bridge chips that are currently being used.

The majority of these systems are basically NAS devices with lots of disk storage. When the next generation of SATA drive comes out in quantity at 320MB you will see extremely cost effective storage. If you look at the 3ware 12-port, it could now support 3.8TB of raw storage in a 2U enclosure. We have already seen two eight-port controllers supporting 16 drives in a 3U which will provide over 5TB in a single box. To just give an idea of the approximate price of 5TB in a system see below.

* 16 x 320MB drives = $4,800

* 2 x 8-port controller = $1,000

* 3U enclosure with 16 drive bays = $1,200

* Motherboard, CPU, Memory = $650

* Various cables and components = $500

* Disk-to-Disk backup Software = $2,500

* Total Approximate Price = $10,700

That is one powerful system for the price and these cost dynamics are what will continue to drive this space. Drive vendors that differentiate product lines for desktop and enterprise might see an advantage with higher reliability drives and higher performance drives, but by definition this is not a 24x7 application and some downtime is acceptable as long as data is not lost (RAID required). Most downtime is managed downtime. SATA will be a benefit in D2D because of the cabling ease of large numbers of drives, but cost will still be king.

Kevin Judd, Senior Product Manager, Procom Technology

Serial ATA will impact disk automation solutions for disk-to-disk (D2D) backup. Serial ATA drives have a number of advantages over standard ATA. They have higher transfer rates; 150MB/sec vs. 133MB/sec with higher speeds planned for development. This means that as the technology progresses, Serial ATA will get increasingly faster allowing the drives to perform similarly to high-end enterprise drives but at a significant cost savings. D2D solutions will become more viable and attractive, providing high performance at a low cost point. Serial ATA drives are also able to be daisy chained, which makes the number of devices per channel higher and allows for easier scalability. Serial ATA drives have hot-pluggable characteristics, allowing additional drives to be added into a system without powering down, which will alleviate extra costs associated with making ATA drives hot swappable for solutions.

Seagate has indicated that it will ship Serial ATA this fall and additional manufacturers are looking towards a December timeframe. Controller cards will be the true pacing factor. Until cheap controller cards are readily available, it is unlikely that there will be wide adaptation of the technology. Widespread adoption will not be seen until mid to late 2003 partly due to a significant inventory and install base of non-serial product. D2D solutions will be the early adopters of the technology due to the fact that they will not be faced with large legacy, or inventory issues and their products are well suited to take advantage of the benefits the technology brings.

Balint Fleischer, Chief Technologist, Network Storage Products Group, Sun Microsystems

ATA drive technology will be a large component in the HSM space providing cost-effective, high-performance, near-line storage. Companies will see this technology emerge mid to late next year. SATA will improve the attractiveness of this low cost technology.