The main purpose of a tape backup is to ensure the safety of your data should a disaster occur which renders access to the files held on the computer impossible. For the most part this works flawlessly, but once in a while a problem can render the data files held on a tape backup, either partially or even totally inaccessible.
A tape backup is usually the last resort for restoring data, so if it failures, it is easy to panic. In most cases, as long as the data was written to the tape data cartridge it will be recoverable. In the situation where somebody overwrites or initialises the data cartridge, this may potentially destroy all the previous data and at best cause the loss of some files. Once failure of the tape drive has been discounted, the best solution is to send your data cartridge for tape data recovery.
In some cases when a tape drive fails it is possible that the most recently written data may be unreadable using a new drive. This was most common in early DDS DAT drives, but with the fine tolerances required, could also occur with more modern tape drives. In these situations a tape drive may need to be modified in order to allow the data to be read back, which requires expert tape data recovery knowledge. In the worst cases failure of the tape hardware may cause damage to the tape media, which could cause further problems when that tape data cartridge is inserted into a new drive.
Physical Media Problems
If the media is physically damaged, either through overuse, a tape from a faulty batch or due to a failure of the hardware, it will cause the backup software to report errors when attempting to restore the data. In these cases it is essential that the raw data held on the tape is secured by a professional data recovery company, in order to avoid further damage occurring.
It may be necessary to avoid damaged areas of the tape media in order to secure the maximum data yield. In rare cases once the good sections of the data have been secured, it may be possible using specialist techniques, to read the data which was previously unreadable.
Backup Data Corruption
The backup software is designed to working faultlessly, but there are a few situations where it may fail to create the backup properly, or not back a file up. One of the most common reasons for a faulty backup is an incorrect tape driver, which could lead to the data being written in a format which is not compatible with the restoration procedure. Another issue is files that are currently open, which can only be backed up if the correct user agent is installed.
Tape Data Recovery
Errors from the backup software may help diagnosis of the problem, but it is only after the tape media and the data stored on the data cartridge are examined that we can determine the exact cause of the issue.
It is important to regularly verify and do test restores of data that is being backed up to tape, in order to ensure no problems exist. This is extremely important whenever any changes have been made to the configuration of the computer or server.