“We called an engineer to repair our server which would not reboot. His tests revealed some disk errors causing a failure of the system, so he recommended DiskEng to us. The service has been excellent, very friendly and professional. Thanks for recovering our server data, allowing us to minimise our downtime.”
David Simons, Confidential, Hendon London
We received a server system containing a pair of 2TB Seagate drives at our laboratory in Oxford from Hendon in London which was configured as a RAID 0 striped array. The hard disk were examined revealing both drives to be in working condition, but contained a number of bad sectors, which caused the server to fail.
Hard disk drives are manufactured with a spare sector area which is used to swap out bad sectors as they are detected, for which a defect list is maintained. This defect list is however only a finite size which will over time become full, at which point any new bad sectors are returned to the operating system, or RAID controller. For any set of hard disk drives operating within the same environment, usually the same drive model and purchased at the same time from a single supplier. It is therefore very common for these defect lists to grow at a similar rate.
Our hardware specialists secured sector-by-sector image copies of the two drives. When there were examined by our RAID recovery specialists, they revealed a RAID 0 striped data array, for which a virtual disk was created. An analysis of the virtual disk revealed two NTFS partitions, a 1TB Windows Server installation, and a 3TB data volume containing 1.8TB of data files. An analysis of the unreadable bad sectors revealed that most were affecting operating system files, and the few affecting the data volume, had damaged unimportant files, which were unnecessary.