By Michael Gallagher, IntelliSuite Technologies
As we meet with more and more clients, it has become very apparent that tape backup is misunderstood in many respects. The two areas of misunderstanding I here most often are tape backup best practices and the total cost of ownership of employing a tape backup solution.
Tape drives have a significantly high failure rate due to improper use and maintenance. The fact of the matter is that most small businesses using tape feel a false sense of security since they are going through the motions and executing their backup strategy. Arguably, the failure rates of tape backup are anywhere from 20% to 70% depending on the source.
The three most common tape backup maintenance issues surround tape rotation, tape drive cleaning, and performing periodic test restores.
There are several different tape rotation philosophies. For small businesses, we recommend a variation of the GFS (Grandfather, Father, Son) methodology. The GFS rotation strategy simplifies tape handling by organizing backups into daily - incremental/differential (Son), weekly - full backup (Father), and monthly - full backup (Grandfather). We advise that you rotate four daily differential tapes Monday through Thursday and 4 weekly full backup tapes on Fridays. If your budget permits, we also advise performing full permanent backups on a monthly basis. In order to ensure business continuity in the case of a disaster, we recommend that your backup tapes are stored off premises. All of your rotation tapes should be replaced annually. The failure rate of tapes begins to increase exponentially after the first year if use.
Tape backup drives should be cleaned at least once per month. Some drive will continue to perform without proper cleaning though more times than not, the data becomes corrupted over time. Lack of proper cleaning is responsible for the majority of tape restore failures.
Over time, problems occur with tapes, tape drives, and backup software. Quarterly tape backup restores allow you to identify issues as they arise. If you are spending the time and money performing the tape backups, you need to verify that your data is intact.
The total cost of ownership (TCO) of your tape backup solution can be determined with a small amount of effort. Tapes drives like most computer devices have a 3 to 5 year lifecycle depending on many factors such as environment, new technologies, data growth, etc. Also, tape drives have moving parts and eventually will just stop working. Backup software has about the same lifecycle as your tape drive provided you have a software maintenance agreement with your backup software provider. Most backup software solutions have annual maintenance or subscription agreements which must be taken into consideration. Next, we have the cost of your tapes which again should be replaced annually. Finally, your time needs to be factored into the equation. How many employee hours does your organization dedicate to changing tapes, cleaning the tape drive, and performing test restores? Adding all of the costs together can give you a high level picture of what your tape backup effort is costing your organization.
One last area to consider when determining the TCO of your tape backup solution is time to restore. How long will you be down and what is the opportunity cost of that outage. This concept is more obscure than the factors previously mentioned but should be taken into consideration when determining the cost of your solution. Some organizations have a significant financial impact when down for an hour or more while others may be able to manage for several days without their data.
If you are going to spend the time and effort with a backup initiative, make sure it is working. If you are considering alternate solutions to tape, take into account all of the costs factors involved before determining which solution is right for you.