Disable external drives from automatically mounting on macOS

README.md

git clone git@gist.github.com:35b1c2781cd7a782cc521a75731b4040.git
ln -s $(pwd)/disable_automount.sh ~/.local/bin/no-mount
no-mount <DISK_NAME>

disable_automount.sh

#!/usr/bin/env bash

# SOURCE: https://akrabat.com/prevent-an-external-drive-from-auto-mounting-on-macos/

FSTAB=/etc/fstab

NAME=$1
if [ -z "$NAME" ] ; then
    echo "Usage: $(basename $0) <DISK_NAME>"
    exit 1
fi

# Add an volume as not auto-mounted to the /etc/fstab file
# by it's identifier. Also pass in the volume name to add a
# comment on that line so that we can identify it later.
add_identifier() {
    ID=$1
    VOLUME_NAME=$2
    if [ -z "$VOLUME_NAME" ] ; then
        echo "add_identifier() takes two parameters: ID and VOLUME_NAME"
        exit 2
    fi

    # get UUID and TYPE from `diskutil info $ID`
    UUID=$(diskutil info "$ID" | grep "Volume UUID" | awk '{print $NF}')
    TYPE=$(diskutil info "$ID" | grep "Type (Bundle)" | awk '{print $NF}')

    # Remove this UUID from fstab file
    sudo sed -i '' "/$UUID/d" $FSTAB

    # Add this UUID to fstab file
    echo "UUID=$UUID none $TYPE rw,noauto # $VOLUME_NAME" | sudo tee -a $FSTAB > /dev/null
    echo "Added $UUID ($VOLUME_NAME) to $FSTAB"
}

# Add all volumes that start with $NAME to the /etc/fstab such
# that they do not automout.

# Get list of identifiers and volume names from `diskutil info`
LIST=$(diskutil list | grep "$NAME")

# Iterate over $LIST
echo "$LIST" | while read -r LINE
do
    # Example of $LINE:
    #    1: APFS Volume Swiftsure Clone - Data 592.1 GB disk4s1

    # Extract disk identifier which is the last field on the line
    ID=$(echo $LINE | awk '{print $NF}')

    # Extract volume name in the middle of $LINE by:
    #    1. remove all characters before $NAME using regex capture assign to $PARTIAL
    #    2. Cut out the last 3 fields (size, units & ID) from $PARTIAL
    #       by reversing, cutting and un-reversing
    [[ ${LINE} =~ ($NAME.*) ]] && PARTIAL=${BASH_REMATCH[1]}
    VOLUME_NAME=$(echo $PARTIAL | rev | cut -d' ' -f 4- | rev)

    add_identifier $ID "$VOLUME_NAME"
done

exit 0