My thinking was that we would get two external HDs that would be exchanged each day (we currently do this with tapes, rotating daily so that every night one tape is offsite with the previous day's backup). The other advantage of adding HDs to our backup system is more storage space. Is there any significant difference in durability between standard external HDs (with 3.5" disks inside), and "portable" external HDs with 2.5" disks inside?
My understanding is that the larger format external HDs are intended primarily for stationary use, so I'm not sure how they would hold up with being carried back and forth every day. On the other hand, the 2.5" "portable" drives are often billed as ideal for additional storage to carry around with a laptop. My boss is the one who usually brings the tape back and forth to the office every day. He doesn't plan on using the external HDs for traveling or carrying around all the time, so he's not too concerned about the larger size and weight. Any insights or suggestions would be appreciated.
The external USB-Firewire drives are all pretty much the same, a SATA or IDE hard disk drive with its own power supply (or not if it is getting its power from the USB device) and connectivity to the host computer. The drives in the systems are standard notebook size 2.5" or desktop-server 3.5" hard drives that can be found in standard systems. They have just been tuned for portability in an external enclosure. The goal here is to keep the drive secure when running, and properly disconnect it (eject) from your system and then store it securely -- out of extremes. The danger with vibration was once considered a huge issue as the heads of the hard disk drive needed to be parked (moved off of the spinning platter itself and parked off to the side of the drive) using a "Park" command from the operating system. Today when the drives are powered down they self-park, preventing any damage to the disk platters themselves. So, you should be protected from any damage or data loss due to the physical packaging itself being damaged. Also, many of the hard disk drives and enclosure can handle some temperature and operational extremes; just make sure to check the specifications before buying. I myself, use a 250GB IDE hard drive in a USB enclosure to back up all of my work on a weekly basis as well as an NAS device for a second set of security for my data. You will also need to see if your backup software can support your USB device for backups. The one thing to realize about this capability, versus a traditional copy or mirror of the data, is that backing up the data will put it into the backup software's archival format, meaning that it will not be readily readable without a restore, so I suggest looking at other solutions, such as mirroring your local drive using the Microsoft Windows Disk Administrator, or a third party solution.
And finally, don't throw out the tape drive, use it for full backups on a monthly basis. It is always good to be protected more than 1X for your business.
One last question -- How big is your data set? If it is relatively small, you may want to look at DVD-ROM options or Blue-Ray Disks as the capacities are getting very sizeable. Blue-Ray can hold 50GBs of data, but the costs are high right now because the economies of scale have not kicked in yet. With DVD-ROM drives the media cost is low and the portability is very high as well as the survivability of the data and you can both take home a copy of the data at night.
This was first published in August 2006