[SOLVED] mounting a scsi disk fails with unknown filesystem error
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In a nutshell sdc1 breaks down to sd i.e. SCSI disk but these days all drives no matter what bus i.e USB, SATA, IDE etc use the SCSI subsystem. The c is the physical drive letter and 1 the partition number. How many disks are installed in your computer.
Post the output of the command fdisk -l (that is a small L). Look at the output of the dmesg command. Did you or was the SCSI controller module automatically loaded? This controller uses the AIC7XXX module. You can look at the output of the lsmod command to verify.
Disk /dev/sdd doesn't contain a valid partition table
Like I said - the disk is blank. You can't mount a blank disk. At a minimum you need to put a filesystem on it (mkfs /dev/sdd should do), or if you want to put multiple filesystems, partition the disk and then put filesystems on the partitions.
It sounds like a misunderstanding of disk formatting... And this has happened ever since MS calls the action of putting a filesystem structure on the disk "formatting".
Low level formatting as done by the scsi utilities does not put a filesystem on the disk.
What it does do is rewrite all sector headers, and record any initially identified bad spots/remap errors. There is no data on the disk other than the sector headers. The utilities can usually perform a read check.. but for a full check it needs to do a write/read check - this records either random data (or writes various test patterns) and reads them back to test for errors. Any errors detected by this are added to the bad block list, and remapped. This is a destructive action that will destroy any data on the disk. You would normally do this AFTER reformatting the disk (the low level format operation). This is done because just rewriting the sector headers doesn't necessarily detect all errors - it only detects those errors that happen to the sector header itself.
The low level format is necessary, but usually done at the factory. With the current data densities it can take a long time to do, and then there is the bad block scan needed afterwards. For small disks (in the 3G size range) it used to take between 45 minutes and an hour and a half. Disks are faster now, but there is also a magnitude (or more) size difference, so doing this can take several hours. In some cases (where there has been no physical damage to the disk) this can recover a good disk and make it usable for quite a while. (The longest I've ever used a disk this way was for 10 years...)
Formatting errors are usually reported as read errors, read parity errors, and header checksum errors. The only way to correct the header checksum errors is through low level formatting. The sector header can be damaged by power failures - this doesn't happen as often now because disks usually have a sufficient capacitor charge to yank the read heads away from the disk (that action first disables the head so that it can't overwrite anything), and that protects the sector headers (and data) from damage. It CAN still happen, but is very infrequent.
I put a filesystem on it using Gparted and it now works fine.
I also tried to run the scsi system on my windows 7 box, but an unpartitioned disk drive attached to the adaptec 39160 controller prevents windows from booting. As soon as I removed the drive, windows booted. So we have a solution in Linux, as Linux will boot with an unpartitoned drive attached to a scsi controller. I suspect there might be other advantages of Linux over win...