Series 4: Ep 7: Debugging Your Code

Don't let errors stop you! This episode focuses on practical debugging techniques for both PowerShell and Bash scripts. We'll intentionally introduce common errors (like typos or wrong parameters) and walk through how to identify and fix them, building crucial troubleshooting skills. Powershell Script: #Script to log multiple event IDs $BeginTime = (Get-Date).AddMinutes(-20) Get-EventLog -LogName "Securityy" -After $BeginTime | Where-Object { $_.EventID -in '4624', '4625'} | Select-Object TimeGenerated, EventID, Message | Format-Table -AutoSize | Out-Files C:\EventLogs_MultipleEvents.txt BASH Script: #!/bin/bash #Variables USERNAME="testuser" # User accountname PASSWORD="P@ssw0rd" # User password GROUP="testgroup" # Custom groupname SSH_DIR="/home/$USERNAME/.ssh" PUB_KEY="ssh-rsa AAAAB3...your-public-key... user@kali" #Step 1: Check ifuser already exists if id "$USERNAME" &>/dev/null; then echo "Error: User '$USERNAME'already exists!" exit 1 fi #Step 2: Create userand set password echo "Creating user '$USERNAME'..." useradd -m -n -s /bin/bash "$USERNAME" # Error 1: -n is an invalidoption if [ $? -ne 0 ]; then echo "Error: Failed to create user'$USERNAME'" exit 1 fi echo "$USERNAME:$PASSWORD" | chpasswd echo "Password set for user '$USERNAME'." #Step 3: Add user tosudoers echo "Granting sudo access to '$USERNAME'..." usermod -aG sudo "$USERNAME" if [ $? -ne 0 ]; then echo "Error: Failed to add'$USERNAME' to sudoers" exit 1 fi #Step 4: Createcustom group and add user echo "Creating group '$GROUP' and adding user..." groupadd "$GROUP" 2>/dev/null usermod -aG "wronggroup" "$USERNAME" # Error 2:"wronggroup" does not exist if [ $? -ne 0 ]; then echo "Error: Failed to add'$USERNAME' to group '$GROUP'" exit 1 fi #Step 5: Setup SSHkey-based authentication echo "Setting up SSH key-based authentication..." mkdir -p "$SSH_DIR" echo "$PUB_KEY" > "$SSH_DIR/authorized_keys" chmod 600 "$SSH_DIR/authorized_keys" chmod 700 "$SSH_DIR" chown -R "$USERNAME:$USERNAME" "$SSH_DIR" if [ $? -ne 0 ]; then echo "Error: Failed to set up SSHkeys" exit 1 fi echo "SSH keys configured for '$USERNAME'." #Step 6: Setpassword expiry to 30 days echo "Setting password expiry policy for '$USERNAME'..." chage -M 30 "$USERNAME" if [ $? -ne 0 ]; then echo "Error: Failed to setpassword expiry" exit 1 fi #Step 7: Logactivity to/var/log/user_setup.log LOG_FILE="/var/log/user_setup.log" echo "$(date) - User '$USERNAME' created and configured" >>"$LOG_FILE" if [ $? -ne 0 ]; then echo "Error: Failed to write logto $LOG_FILE" exit 1 fi #Step 8:Confirmation Message echo "Testing SSH connection to '$USERNAME'@localhosts..." ssh "$USERNAME@localhost" if [ $? -ne 0 ]; then echo "Error: SSH connection failed." exit 1 fi echo "User '$USERNAME' created and configured successfully!"