[Read part 1 of the interview here].
Catastrophic disasters are often the reason that tape is used as an offsite backup media, but sometimes tapes can be within a disaster area or be affected by flood, fire or earthquake. Doug Owens, Manager of Technical Services for CBL Data Recovery Technologies , led the recovery team for the tape archive of a major Brazilian bank that had both its mission critical IT systems and offsite tape backup set damaged by massive floods in 1999.
Owens said, The customer had lost hundreds of thousands of account details and transaction records and we started getting boxes of waterlogged tapes. In this case we had advised them to leave the tapes in the boxes as although water would cause the tapes to rust slightly, we believed the damage would be less than if they were exposed to air, which quickly causes oxidisation."
In this case we had to manually clean hundreds of tapes in a special solution to remove silt from the flood water and then dry and read the tapes in modified systems we recovered about 70% of the data which included the most mission critical items.
Fire and smoke
Fire and smoke is also a major problem. The thin film of a tape is very sensitive to heat and can melt very quickly even with a small rise in temperature. Additionally, smoke from a nearby fire causes minute particles that are attracted to the magnetised tape and then distributed to any drive used by the tape. The same process applies to fire damaged drives that can damage any tape placed into them.
Tapes are generally resistant to shock such as earthquakes but before you go throwing them around the office, some of the newer models such as AIT and LTO have built in sensors which can be damaged by a sudden jolt causing them to refuse to read until these sensors are replaced or repaired, Owens explained.
First steps to fixing a problem
The very first step when you think you have a problem with a tape or tape drive is to not make the problem any worse. It always best to contact the drive and software manufacturers technical support before you start doing anything else. This support is normally part of a maintenance contract or via the warranty, says Owens.
If a tape is stuck, dont try and force it out let the manufacturer or agent do this as there maybe repercussions to the drive or the tape (or even the warranty) if you attempt to do this yourself. If a tape is snapped or de-spooled by a drive, then assume that this may well happen to the next tape you place in the unit. Owens recounts, We had one customer who de-spooled six tapes we thought he may have stopped after the first 2 tapes were damaged but he assumed that it was the tapes and not the faulty drive problem that it turned out to be.
If a tape is damaged by fire, flood or heavy dust/particle contaminant, Owens recommends that you do not test it in your active tape unit as this may cause further damage to the drive and subsequent tapes.
More often, a problem that appears to be hardware-based is often a small software issue; We have had issues when an IT manager leaves a company and then soon after we get a job where a number of tapes appear to be corrupted or unreadable. The problem often turns out to be that the new IT manager is actually using a different piece of software for data backup or special settings have been changed but not documented.
Owens recommends to many customers that tape backup procedures be maintained in an ongoing log which records software, hardware and settings in both a paper based and electronic format, preferably kept both on and offsite. If a worse case scenario does happen and a data archiving area is destroyed or damaged beyond use, this log can be used to re-build an identical system.
Owens concludes, Tape is still the best medium for long term storage of data. It has a factor of reliability several times the magnitude of disk systems but, like all technology, it will fail. The best advice I can give, is to treat tape technologies with respect and care, and you will probably never have to call us at CBL but, if you do, we will do the best we can to help.
[Read part 1 of the interview here].
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