We’re getting ready to upgrade servers at work and will be mothballing our old server once done. I want to clean up the old server by deleting files and wiping out old data completely. What do you guys recommend for completely erasing deleted files from the hard drive so they can never be salvaged? We do not want to destroy some data (meaning I don’t want to wipe the hard drive completely), but we want to make certain that anything I delete cannot be recovered by any type of software or diagnostics. Suggestion?
Without formatting, I don’t think its possible… whenever you delete something from solid state memory, nothing is actually removed… its the location of the something that gets removed.
I believe (although I may be wrong) the only thing you can do is backup the files you want to keep, format, then reload.
I’m hoping to avoid this. If you are correct and it cannot be removed, can that data be scrambled?
I wouldn’t be calling a HD “solid state”, but you’re otherwise correct. It would help to know what OS you’re using with what filesystem format. (Win2k with NTFS? Linux on ext2?). On FAT systems, files deleted have the first character of their file entry changed to “?”. You may recall in the olden days having to enter the first character of files you were trying to recover with UNDELETE.EXE; it’s 'cause that char was gone.
If you’re not gonna be hanging on to the server, I’d recommend re-formatting (perhaps with something like Linux fsck, which can write alternating bits to disk). If not, I’d look for some type of file deletion program (perhaps like some listed here, by random Googling). They do stuff like overwriting the sectors the file used with 1s, 0s, then alternating 1s&0s. Can’t get that back.
If you wanna be ultra cheesy (but simple), just delete the files, then fill your drive up with mp3s or something, then delete them all. That’ll make sure the sectors that did hold someones credit card numbers now contain the worthless voice of Cher.
A note on formatting: Simple formatting can actually be undone. I’d recommend using a low-level type format if you do that.
I believe PGP has a file erase feature that fills the disk with random 1’s and 0’s. Norton Utilities also used to have this feature.
You don’t want to destroy all the files? Move the ones you want to keep to another disk, then nuke the server.
If it’s an Intel x86 based machine (as opposed to Sparc, DEC Alpha, etc) and can boot from a floppy, have a look at Autoclave
Not sure if this will work on SCSI drives.
How important is it that the files are never recoverable? If the company would be sued to death, or otherwise suffer losses, consider simply buying new drives, followed by physical destruction of the old drive platters. Most newer drives use glass platters, which shatter nicely when hit hard.