$ grep -rnw '/media/boot/' -e 'UUID'; grep -rnw '/etc/' -e 'UUID' 2>/dev/null; sudo blkid | grep mmcblk0
# results
/media/boot/boot.ini:166:setenv bootrootfs "console=tty1 console=ttySAC2,115200n8 root=UUID=e139ce78-9841-40fe-8823-96a304a09859 rootwait ro fsck.repair=yes net.ifnames=0"
/media/boot/boot.ini.default:34:#bootrootfs=console=tty1 console=ttySAC2,115200n8 root=UUID=e139ce78-9841-40fe-8823-96a304a09859 rootwait ro fsck.repair=yes net.ifnames=0
/etc/fstab:1:UUID=e139ce78-9841-40fe-8823-96a304a09859 / ext4 errors=remount-ro,noatime 0 1
/etc/fstab:2:UUID=52AA-6867  /media/boot vfat defaults 0 1
/dev/mmcblk0: PTUUID="3cedfd53" PTTYPE="dos"
/dev/mmcblk0p1: SEC_TYPE="msdos" LABEL="boot" UUID="52AA-6867" TYPE="vfat" PARTUUID="3cedfd53-01"
/dev/mmcblk0p2: LABEL="rootfs" UUID="e139ce78-9841-40fe-8823-96a304a09859" TYPE="ext4" PARTUUID="3cedfd53-02"