On Thu, Apr 15, 2021 at 02:36:37PM -0500, Charles Zeitler wrote: > disks are raid5, i don't know which are /dev/sdb /dev/sdc etc. > is this going to be an issue?
Nope. Hugo. Oh, all right, I'll explain... The superblock on each device contains the UUID of the filesystem and a device ID (you can see both of these in the output of btrfs fi show). When btrfs dev scan is run (for example, by udev as it enumerates the devices), it attempts to read the superblock on each device. Any superblocks that are found are read, and the UUID and devid of that device node are passed to the kernel. The kernel holds a lookup table of information for every device known of every filesystem, and uses that table to work out which device nodes it needs to use for any given FS. Hugo. -- Hugo Mills | Guards! Help! We're being rescued! hugo@... carfax.org.uk | http://carfax.org.uk/ | PGP: E2AB1DE4 | The Stainless Steel Rat Forever
