Back in my earlier days of computing (the 80's) there were DOS utilies that could access the areas (sectors and clusters) reserved on a media for such things as FAT tables and table logs of bad spots on a disk whether it be a floppy or harddrive. These areas also contain info such as media type, manufacturer etc. These areas are not reachable via the regular explorer access. I believe all medias are assigned a s/n by the format process when they are formatted. Since using windows I have lost interest in these type of utilies but I believe they are still out there.

Numbers on micro sd cardsHow to change sd card serial numberSerial

Transcend is a globally recognized leader in the manufacture of storage, multimedia and industrial products. Established in Taiwan, Transcend offers a full line of memory modules, flash cards, USB flash drives, portable hard drives, solid state drives, car video recorders, Apple solutions, industrial solutions, and more.

I use to use one to create a catalog of what programs were on my disks just by insertting them into the drive via a 'MS Basic program'. This is why a disk cannot be fixed that has a damaged MBR (Master boot record). Most other bad spots on a disk will be flagged as 'Not Usable' when you format a disk. This is transparently done on format. Also this is the main purpose of 'Scandisk' with the repair option turned on. Maybe still do-able with a 'Basic program'.

I can't seem to find a way to find the serial number of my SD card. I've looked in /dev/disk/by-uuid, but the same uuid is used across multiple Pis that I have. I've also used the blkid command, but I can only seem to get the size of the SD card. Any help would be appreciated. Edit: I managed to figure out where the 'serial number', aka CID, is found.

Samsung Sd Card Serial Number Check

For anyone who's interested, it's located in /sys/block/mmcblk0/device/cid. The CID contains info on when the card was manufactured, by whom and what its intended content is. For more information on the SD card standard I plan on using the CID to encrypt the files on the SD card so no one can take my card out and simply copy what's on it.