Dumping Guides/Linux Advice

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Exclusive access to disc drive

If you're dumping via Linux, while not required, this will save you lots of time and effort, and will fix any issues you may be having with your system taking a while to let you start dumping from your drive, or not allowing you to dump altogether, on certain discs:

- Get your drive's device ID by checking dmesg -w, or by doing ls /sys/bus/scsi/drivers/sr. It'll look something like 0:0:0:0

- Do echo -n "0:0:0:0" > /sys/bus/scsi/drivers/sr/unbind (root permissions required)

This unbinds the kernel's sr device driver for this drive, until you reboot, unplug and replug it, or just bind it back again via echoing to bind instead of unbind

Because of this, /dev/sr[x] no longer exists for this drive, so you'll have to specify your drive via the generic SCSI device path, /dev/sg[x]

i.e. ./redumper --drive=/dev/sg0

Getting cheap IDE->SATA adapters to work

If you connect to your old IDE drive through a IDE-SATA adapter, you can end up in a situation where your CD drive looks like a hard drive in Linux. It'll look something like this in dmesg when you insert a CD (example here is IDE->SATA->USB):

[ 8200.963837] usb-storage 6-2.3.1:1.0: USB Mass Storage device detected
[ 8200.964252] usb-storage 6-2.3.1:1.0: Quirks match for vid 1e91 pid de2c: 900000
[ 8200.964381] scsi host0: usb-storage 6-2.3.1:1.0
[ 8202.007684] scsi 0:0:0:0: Direct-Access     ASMT     2115             0    PQ: 0 ANSI: 6
[ 8202.008911] sd 0:0:0:0: Attached scsi generic sg0 type 0
[ 8202.010488] sd 0:0:0:0: [sda] Spinning up disk...
[ 8203.030395] ........................ready
[ 8229.346098] sd 0:0:0:0: [sda] 303592 2048-byte logical blocks: (622 MB/593 MiB)

You can see it shows up as /dev/sda instead of /dev/sr0.

If this happens, you can usually rectify it by running the command rescan-scsi-bus.sh --forcerescan (It's part of sg3_utils).