Before writing an ISO to USB, you need to correctly identify your USB device path. Run:

lsblk -f

This will list all block devices. Your USB typically appears as /dev/sdX where X is a letter (like sdb or sdc). Be absolutely certain of the device name - writing to the wrong device can destroy data.

The most direct way uses the dd command:

sudo dd if=your-image.iso of=/dev/sdX bs=4M status=progress oflag=sync

Breaking this down:

• if= specifies input file (your ISO)
• of= specifies output device (your USB)
• bs=4M sets block size for better performance
• status=progress shows transfer progress
• oflag=sync ensures proper syncing

If your dd lacks status=progress, pipe through pv:

pv your-image.iso | sudo dd of=/dev/sdX bs=4M oflag=sync

For systems without dd, use cat:

cat your-image.iso | sudo tee /dev/sdX >/dev/null

After writing, verify the checksum:

sha256sum your-image.iso
sudo dd if=/dev/sdX bs=1M count=$(stat -c%s your-image.iso)/1048576 | sha256sum

The SHA256 hashes should match.

While you mentioned preferring CLI, these GUI tools have CLI options:

# For USB Creator
sudo usb-creator-cli --install=y --volume=/dev/sdX --image=your-image.iso

# For UNetbootin in CLI mode
sudo unetbootin installtype=USB targetdrive=/dev/sdX method=diskimage isofile=your-image.iso

For scripting purposes, here's a complete bash function:

function write_iso_to_usb() {
    local iso_path=$1
    local usb_device=$2
    
    if [ ! -f "$iso_path" ]; then
        echo "Error: ISO file not found"
        return 1
    fi
    
    if [ ! -b "$usb_device" ]; then
        echo "Error: USB device not found"
        return 1
    fi
    
    echo "Writing $iso_path to $usb_device..."
    sudo dd if="$iso_path" of="$usb_device" bs=4M status=progress oflag=sync
    
    echo "Verifying checksum..."
    local original_hash=$(sha256sum "$iso_path" | awk '{print $1}')
    local written_hash=$(sudo dd if="$usb_device" bs=1M count=$(stat -c%s "$iso_path")/1048576 | sha256sum | awk '{print $1}')
    
    if [ "$original_hash" = "$written_hash" ]; then
        echo "Verification successful"
    else
        echo "Verification failed!"
        return 1
    fi
}

For creating persistent live USBs from CLI:

sudo mkdir /mnt/{iso,usb}
sudo mount -o loop your-image.iso /mnt/iso
sudo mkfs.ext4 -L liveusb /dev/sdX1
sudo mount /dev/sdX1 /mnt/usb
sudo rsync -a /mnt/iso/ /mnt/usb/
sudo dd if=/dev/zero of=/mnt/usb/casper-rw bs=1M count=2048
sudo mkfs.ext4 -L casper-rw /mnt/usb/casper-rw

• If USB isn't bootable: Try sudo parted /dev/sdX set 1 boot on
• For larger ISOs: Format USB as NTFS first with sudo mkfs.ntfs -f /dev/sdX1
• If write seems stuck: The sync operation might take time with large ISOs

Before writing an ISO, you need to identify your USB device path:

lsblk
sudo fdisk -l

Look for your USB device (typically /dev/sdX where X is a letter). Be extremely careful - selecting the wrong device can wipe your system.

The most straightforward method uses dd:

sudo dd if=your_image.iso of=/dev/sdX bs=4M status=progress oflag=sync

Key parameters:
- bs=4M: Sets block size for faster transfer
- status=progressoflag=syncUsing pv for Progress Monitoring

pv your_image.iso | sudo dd of=/dev/sdX bs=4M oflag=sync

cat your_image.iso | sudo tee /dev/sdX >/dev/null

sudo cp your_image.iso /dev/sdX
sync

sha256sum your_image.iso
sudo head -c $(stat -c%s your_image.iso) /dev/sdX | sha256sum

sudo isohybrid your_image.iso

sudo add-apt-repository ppa:mkusb/ppa
sudo apt update
sudo apt install mkusb
sudo mkusb /path/to/iso