Frequently Asked Questions

What is SATA? Serial ATA or Advanced Technology Attachment drives. Sometimes also known as IDE or Integrated Drive Electronics. The previous generation of ATA technology was parallel ATA. The new Serial ATA devices are faster, and allow for easier connectivity through a connector with a smaller form factor.

Why SATA over SCSI or fibre Channel? A mirrored pair of SATA drives can beat a single SCSI or fibre Channel drive in price, performance, reliability and capacity. The TerraBlock system is designed to aggregate the bandwidth of several SATA drives to equal or surpass fibre or SCSI solutions.

How do the clients connect? The clients connect via 2Gbit or 4Gbit fibre channel, with allowable length of 150 to 300 meters. Unlike SCSI, fibre channel lets you centralize the hard drive storage away from the clients, while leaving the workstation in the room for easy access.

Why fibre Channel? fibre Channel allows the highest sustained bandwidth that is easily networked with low-cost components. Other common connectivity types are SCSI, Ethernet and iSCSI. These work well for local attached solutions, or fully network enterprise solutions, but all have limitations that cannot be overcome easily to provide the dedicated quality of service that fibre channel provides.

Why 2Gbit or 4Gbit? fibre channel started out as a 1Gbit protocol in this industry, but has since doubled twice and increased to 800MB/sec full duplex. The advantage of moving up in speed is in the efficiency of using a single cable on a single channel to produce the bandwidth you need, without having to stripe volumes across multiple channels. For standard definition, 4Gbit speeds may not be necessary, but investing in the architecture now future-proofs your facility for HD and beyond.

Is there anything to install on the clients? No. In most configurations there is no installed client software. The client management software is presented to the client from the server. This allows the TerraBlock system to be seen as generic attached storage instead of network storage, which has incompatibilities with certain applications. Also, without installed client software, TerraBlock volumes can be used in conjunction with other SAN solutions that install software, without conflict.

Is TERRABLOCK like a JBOD? TerrraBlock has several advantages over a simple JBOD, the first being that the Facilis solution incorporates the drives, a server, multiple client connectivity and sharing software in one package. In order to do this with a "storage only" solution like a JBOD, you would have to purchase several components, usually from several different vendors.

Is TERRABLOCK like a SAN? The average SAN uses fibre drives or fibre attached RAIDs, a fibre switch and client software. This solution is good, but can include many different components, often from many different vendors. Since we're integrated into a single chassis, Facilis has the ability to achieve a similar workflow for a small fraction of what many other solutions would cost for an equal client count, aggregate bandwidth and capacity.

Is TERRABLOCK like a NAS? Network Attached Storage uses Ethernet attachment to clients. It's a good solution as well, but limited in bandwidth and scalability. In addition, many applications will not operate properly with Ethernet connectivity unless it's a proprietary solution. TERRABLOCK provides a higher bandwidth per client; higher overall system bandwidth for more finishing clients; and simple, dedicated wire-speed connectivity.

What clients does TERRABLOCK support? TerraBlock supports all Avid editors on Windows 2000, Windows XP, Mac OS9 and Mac OSX, as well as Apple's Final Cut Pro on OSX. In addition, many popular graphics and animation packages are supported, or any application that works with local storage.

What's a "Virtual Volume"? When a volume can be created from a "pool" of disks instead of a physical location on a single disk, the volume is considered "Virtual". These volumes can be created and deleted on the fly without having to re-stripe the disks or format a RAID set. More volumes can be created incrementally as more storage is needed, instead of trying to guess the future needs of a project or edit room during initial setup.

How is the data protected? Dyna-RAID allows you to choose between RAID5 partiy or RAID1 mirroring protection. RAID5 parity protection allows efficient use of available storage while giving data protection, whereas RAID 1 mirroring protection affords you the the highest performance while giving data protection. A 12TB TerraBlock system can have as many as 250 unique virtual volumes, any number of which can be RAID1 or RAID5 protected or un-protected (RAID0) based on the needs of the project or facility.

Mirroring important data allows the clients to sustain normal workload even if a drive failure occurs, and to do so during recovery. To achieve this high level of performance in mirroring mode we use a selective mirroring scheme, similar to RAID 0+1. Other RAID solutions have more difficulty sustaining throughput after a drive failure and during recovery. Also, hardware RAID controllers can limit future performance enhancements that will be available through changes in the software protection and increase in processor speed.

How do you scale up the capacity? The TerraBlock system uses additional server units to scale up the capacity, bandwidth and client count. We achieve this by using a low-cost 2Gbit fibre channel switch. When the connected clients are attached to the switch, they are able to see both servers on the same network. In the future, this will give us the opportunity to mirror data across multiple server units to ensure our customers will have access to their data, even in the unlikely event of a server failure.

What's the highest data rate the server can provide? We normally don't rely on performance numbers, since those numbers often give a false indication as to the ability of a SAN to sustain a heavy load from multiple clients. However, a single client over a single 4Gbit fibre connection to a single server could sustain over 380MB/sec in writes, and over 360MB/sec on reads. That number increases to over 600MB/sec across a full 24D when two clients are accessing the server simultaneously on sequential reads. This can be increased ever further when using the Tandem feature to use multiple servers to create a spanned volume that combines the performance of the servers.