Case:
HP388 G8 server, the bottom layer is RAID5 made of 6 SAS 500GB disks.The operating system is RHEL 5.5, which stores a background of the company’s application to a large number of PHP web files and mysql databases.RAID’s multiple disk faults are offline, causing RAID to collapse. When the administrator attempts to restore RAID later, the RAID operation has been reconstructed, but the data still cannot be restored.
Solution:
1. The engineer first performs a complete mirror of all disks, which is a backup process, and it is also a process of comprehensively detecting the disk.The detection found that there were two disks with serious physical bad channels. You had to use a dedicated device to use the damaged disk for data mirrors.2. After the mirror is completed, start analyzing the disk data. Use the structure of the EXT3 file system to restore the location of the original disk on the RAID position and the size of the band. Use a special software to perform the virtual RAID combination of 6 disks.The original raid data.3. Analyze the virtual original RAID data, and find that the data of the first two blocks (256MB) have severely damaged the data. It is estimated that the initialization operation of RAID did the RAID operation.Stopping the bad sector, otherwise it will be destroyed.4. The engineer fixed the EXT3 file system in the entire RAID. After repair, about 99.9% of the data was restored. The customer expressed very satisfied.