Removable disks provide simple and effective storage. But are removable disks a viable storage replacement for tapes in the SMB space? In this FAQ, noted SMB storage consultant, Tory Skyers, discusses removable disk storage. His answers are also available below as an MP3 download.
Table of contents:>>The pros and cons of removable disk >>Portability advantages of removable disks >>Available removable disk technologies >>Removable disk capacity >>Removable disk backup and recovery speeds >>Replacing tapes with removable disks
For SMBs, simplicity and ease of use are a paramount. They keep costs down and SMBs traditionally do not use a large IT staff to support their systems. So the biggest pro for removable disks are their simplicity and their ease of use to set up and maintain.
The cons are essentially cost. Once you start getting into large data backup sizes like multiple gigabytes, you have to have someone there to change out the cartridges once they fill up, which in turn causes the costs to start adding up.
Removable disk media is relatively expensive when compared to tape. So I'd book cost as the major con.
This kind of blurs the lines because the same portability advantages that tapes hold, removable disks hold as well. You can take them offsite or even store them onsite in a different room or firebox. You can also take them home or take them to your office. Portability gives you piece of mind. And piece of mind, when it comes to SMB-level data, is worth its weight in gold.
The old man of the bunch is Iomega (an EMC Corp. company). Iomega has been around forever and I think everybody is familiar with the Iomega Zip, which they're still making, believe it or not. Iomega has another drive called the Rev, which has taken over for the Jaz as their higher end model.
There is also company by the name of RDX Storage that makes a disk-to-removable device that you can put in your rack.
There are also OEMs out there that are manufacturing hard disk docks that technically allow you to take any hard disk drive off the shelf, whether it be a 2½ inch or 3½ inch drive or solid-state drive (SSD), plug it into these docs, and essentially have a removable disk system.
The capacity goes from relatively small, like the Iomega Zip which is around 120 MB, to the mid-level range of about 120 GB for the Rev, all the way up to the 1.5 TB of the 3½ inch SATA hard drive.
Removable disk really runs the gauntlet as far as capacity is concerned and you'll be able to pick and choose what best fits your needs.
Data backup and recovery speeds are really dependent on a lot of small variables. At a high-level, you can count on, at the least, USB speeds for backup and recovery. SATA speeds can be achieved for some of the higher end devices, like the Rev and the RDX offering.
For the most part, the removable drives today are really fast. They're a hard drive-based technology and they're using the advanced buses. So they're really fast and you'll rarely see an issue as far as speeds are concerned with today's removable disks.
This is a very difficult question and people familiar with the zip drives and the direct-attached storage (DAS) drives ask me this all the time. For whatever reason, there's still a lot of bad sentiment toward tape out there.
I'd have to say no. I would suggest that removable disks be used to augment whatever offsite, long-term or archival data protection you have. While the drives might be slightly more expensive than removable disks, the tapes are cheaper per gigabyte than the removable drive and they're also more durable.
If you drop a traditional 2½ inch or 3½ inch hard drive, that's it. You can drop a tape and kick it around a little bit before it's actually destroyed. So as far as a replacement is concerned, if it were my data, I wouldn't replace it. But there is a case to be made where you can use them to augment your traditional data protection or replace some of the smaller, more speed-sensitive needs for an SMB.Tory Skyers is a senior infrastructure engineer and storage consultant, primarily focusing on the SMB space.
This was first published in April 2009