Key in this section is to define what events trigger the recovery process? These can vary from the recovery of a single file to the recovery of a whole disk. In any event, the process for obtaining the latest tape or CD from the media store, loading it on the drive and then transferring the files to be recovered to the spectrometer database. There also needs to be a verification step to ensure that the file or files have been correctly copied back to the system.

Table II. Example of a basic system backup log

Documented Evidence To ensure that there is evidence that the procedure has been followed a backup and recovery logs are required. For practical purposes we'll look at backup only as recovery is simply the mirror image of backup. At its simplest this is a record that each backup has been performed without error by looking at the log or file produced by the backup software after each backup. The person (user of IT depending if the system is standalone or networked) looks at the log file produced by the backup software to check if there are no problems recorded in it. If there are no issues, then the paper backup log is noted for June 10, 11, and 13. However if there is a problem as seen on June 12 with write errors on the tape; then the tape is replaced and the backup is repeated. This is one way to approach the issue of a failed backup.

Another way, if documented in the procedure, is that the users may take the view that the backup can go for another 24 h before the backup is repeated. Here, the risks of not backing up immediately following a media failure must be balanced with the time taken out of the working day to ensure that records are preserved. This is your laboratory's judgement call, not mine.

Service Level Agreement Whatever requirements are needed for the backup and recovery of a networked spectrometer system, they need to be incorporated in an SLA so that the IT department have a standard to work against. The SLA can also provide a standard or benchmark for QA to audit against, providing that the agreement has specific and measurable performance criteria.

The SLA with the internal or outsourced IT department should cover and document the following parameters as a minimum:

• Backup schedule
• Definition of the software and records to be backed up and the frequency of each
• Recovery procedures

The content of an SLA is outside of the scope of this discussion and the reader is referred to the book by McDowall (1) for further information.

Reference 1. R.D. McDowall, Validation of Chromatography Data Systems (Royal Society of Chemistry, Cambridge, UK, 2005).

R.D. McDowall is a visiting senior lecturer in the Department of Chemistry at the University of Surrey, principal of McDowall Consulting (Bromley, UK), and "Questions of Quality" column editor for LCGC Europe, Spectroscopy's sister magazine. Address correspondence to him at 73 Murray Avenue, Bromley, Kent, BR1 3DJ, UK.