Plug in your USB drive and check system messages:
# dmesg sd1 at scsibus2 targ 1 lun 0: <Vendor, Model, 1.26> SCSI3 0/direct removable serial.12345678901234568789 sd1: 7633MB, 512 bytes/sector, 15633408 sectors
# disklabel sd1 ... size offset fstype [fsize bsize cpg] a: 736256 1024 4.2BSD 2048 16384 16142 c: 15633408 0 unused i: 960 64 MSDOS
Let's say you want to mount the first partition (
a:), then the device
you're looking for is
/dev/sd1a. Create the mount point directory, say
/mnt/usb-drive, and mount the drive:
# mkdir -p /mnt/usb-drive # mount /dev/sd1a /mnt/usb-drive # ls /mnt/usb-drive ...
Hooray! Now it's mounted.
Before disconnecting the drive from the USB port, make sure it's unmounted, to that you'll need to leave mount point directory and then use it as an argument for unmount(8).
# cd # umount /mnt/usb-drive #
Or you can address your device directly:
# cd # umount /dev/sd1a #
If you'd like to automate these steps, check
functions from my ~/.profile.
Tested on OpenBSD 6.3.