Enhance backup server - recreate user home folders (after wiping/replacing the backup disk/mount)

recreate_enhance_backup_user_home-folders.sh

#!/bin/bash

declare -a users_to_create

echo "Scanning for users with missing home directories..."

while IFS=: read -r username _ uid gid _ homedir shell; do
    # Ignore system users (UID < 1000), but include UID 0 (root)
    # Also skip 'nobody' (UID 65534) and users with non-functional home directories
    if [[ ("$uid" -ge 1000 || "$uid" -eq 0) && "$homedir" != "/nonexistent" && "$uid" -ne 65534 ]]; then
        if [[ ! -d "$homedir" ]]; then
            users_to_create+=("$username:$uid:$gid:$homedir")
        fi
    fi
done < /etc/passwd

missing_count=${#users_to_create[@]}

if [[ $missing_count -eq 0 ]]; then
    echo "All user home directories are present. No action needed."
    exit 0
fi

echo "$missing_count home director$( [[ $missing_count -eq 1 ]] && echo 'y' || echo 'ies' ) missing:"
for entry in "${users_to_create[@]}"; do
    IFS=: read -r username uid gid homedir <<< "$entry"
    echo "  - User: $username (UID: $uid, GID: $gid) -> $homedir"
done

read -p "Proceed with creating these directories and setting ownership? (y/N): " confirm
if [[ "$confirm" =~ ^[Yy]$ ]]; then
    for entry in "${users_to_create[@]}"; do
        IFS=: read -r username uid gid homedir <<< "$entry"
        echo "Creating $homedir for $username..."
        mkdir -p "$homedir"
        chown "$uid:$gid" "$homedir"
    done
    echo "All missing home directories have been created and ownership set."
else
    echo "No changes made."
fi