Storage server synergy
Pogo Linux StorageWare S316 pairs SATA and Linux for price-wise performance
In addition to exceptional storage density, SATA (Serial ATA) RAID brings SCSI-like performance and reliability to dirt-cheap disk drives. Combine SATA disks with Linux on Intel hardware and you’ve got a foolproof formula for price/performance ratio. Pogo Linux has poured these ingredients into a line of file servers that allows IT shops to meet fairly demanding storage requirements at bargain-basement prices.
I reviewed Pogo’s StorageWare S316. Like your average 3U rack-mount server, the S316 sports dual Xeon processors and as much as 16GB of RAM. What’s unusual about the S316 is the disk capacity. It comes with 16 160GB Seagate hot-swap SATA drives attached to two 3Ware RAID controllers, for a total drive capacity of 2.24TB of raw capacity (slightly more than 2TB when formatted).
The 3Ware cards put each drive on a separate SATA channel. With hot-swap support and very high throughput — almost 160MBps sustained — they deliver performance comparable to high-end SCSI RAID solutions at a much lower price, starting at less than $10,000 for 2.2TB with 512MB RAM and dual 2.4GHz Xeon processors. The S316 provides as much connectivity and expandability as one could wish for, with dual integrated GbE adapters and six PCI slots: two 64-bit 133MHz PCI-X, one 64-bit 100MHz PCI-X, and three 64-bit 66MHz PCI-X (two slots are used by the 3Ware RAID controllers).
The S316 should serve well in any organization using Linux. The Red Hat Linux 9 software is preconfigured with the ext3 journaling file system for secure, stable file operations and quick recovery after errors. The kernel is version 2.4.20-13.9smp, and server software includes Apache2 Web server, BIND (Berkeley Internet Name Domain) DNS server, DHCP server, Fetchmail mail retrieval, MySQL database server, Postfix mail server, PostgreSQL database server, FTP server, Procmail mail filter, Samba Windows file sharing, Sendmail, and the Squid proxy server. Pogo will also install LVM (logical volume manager) if desired, allowing for a great deal of flexibility in managing partitions and volumes. (The current version of Linux doesn’t support volumes of more than 1TB, but the 2.6 kernel will.)
The system also comes with two Webmin Web-based remote administration consoles. A custom version called PogoConf allows GUI administration of the network cards, storage, 3Ware RAID configurations, Samba, and NFS (Network File System) shares. And a basic version of Webmin allows you to perform any administrative task that could be done with the Linux GUI, including terminal sessions, file management, hardware and server software configuration, boot-up and shutdown scripts, etc.
The combination of the two consoles yields usability and easy administration that is exceptional for any server OS, especially Linux. When the system is started, there’s no need to be near it again; even BIOS configuration can be done remotely.
Opening the chassis reveals a very clean system. The SATA drive cables use far less space than ATA or SCSI ribbon cables. In the S316, they are well-secured and provide lots of room for air to cool the drives and processors. Ten fans (including six hot-swap modules) will keep the system cool even in a fully loaded rack. The hot-swap drives are easy to remove, with positive latches that are easy to engage. Each drive has both power-on and activity lights, making it easy to tell if a drive is having problems or is not properly seated.
Setup and configuration is easy and well-documented with help files available through the Web console. In my testing, the server saturated a GbE connection during file transfers and recorded more than 16,000 I/Os per second using 64KB blocks. Throughput in file transfers was very close to 160Mbps, which is about the best that you can get, even from SCSI or 1Gbps FC (Fibre Channel).
The Pogo Linux StorageWare S316 offers terrific expansion, good redundancy, and performance comparable to large, expensive SCSI-based servers from big manufacturers, at a price that’s less than half of what you might expect. It should be on the short list for any shop running file servers or database servers on Linux. The price makes it attractive to smaller organizations; the performance, expandability, and redundant hardware options make it a fit in departmental or even enterprise applications.