Configure SSH integration for the Datadog agent on servers managed by Laravel Forge

setup_datadog_ssh.sh

#!/bin/bash

# Configure SSH integration for the Datadog agent on servers managed by Laravel Forge.
#
# -------------------------------
# Usage:
# 1. Configure Datadog SSH integration file in /etc/datadog-agent/conf.d/ssh_check.d/conf.yaml:
#  
#  instances:
#  - add_missing_keys: true
#    host: localhost
#    private_key_file: /opt/datadog-agent/.ssh/id_rsa
#    username: forge
#
# 2. Download and run this script:
#  
#  chmod +x setup_datadog_ssh.sh
#  sudo ./setup_datadog_ssh.sh
# -------------------------------

set -e  # Exit on error

# Color codes for output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m' # No Color

echo -e "${YELLOW}═══════════════════════════════════════════════════════════${NC}"
echo -e "${YELLOW}SSH Configuration for Datadog Agent${NC}"
echo -e "${YELLOW}═══════════════════════════════════════════════════════════${NC}\n"

# Variables
DD_AGENT_HOME="/opt/datadog-agent"
DD_AGENT_SSH="$DD_AGENT_HOME/.ssh"
FORGE_SSH="/home/forge/.ssh"
PRIVATE_KEY="$DD_AGENT_SSH/id_rsa"
AUTHORIZED_KEYS="$FORGE_SSH/authorized_keys"

# Function to execute commands with feedback
run_command() {
    local description=$1
    local command=$2
    
    echo -e "${YELLOW}→${NC} $description"
    if eval "$command"; then
        echo -e "${GREEN}✓${NC} Complete\n"
    else
        echo -e "${RED}✗${NC} Error during execution\n"
        exit 1
    fi
}

# Step 1: Import private key
run_command \
    "Creating SSH directory for Datadog agent" \
    "sudo mkdir -p $DD_AGENT_SSH"

run_command \
    "Copying private key from Forge" \
    "sudo cp $FORGE_SSH/id_rsa $PRIVATE_KEY"

# Step 2: Convert key to PEM format
run_command \
    "Converting key to PEM format (required by Paramiko)" \
    "sudo ssh-keygen -p -m PEM -f $PRIVATE_KEY -N ''"

# Step 3: Create known_hosts file
run_command \
    "Creating known_hosts file" \
    "sudo -u dd-agent ssh-keyscan localhost | sudo -u dd-agent tee $DD_AGENT_SSH/known_hosts > /dev/null"

# Step 4: Add public key to authorized_keys
run_command \
    "Adding public key to authorized_keys" \
    "sudo ssh-keygen -y -f $PRIVATE_KEY | sudo tee -a $AUTHORIZED_KEYS > /dev/null"

# Step 5: Configure permissions
run_command \
    "Configuring SSH directory ownership" \
    "sudo chown -R dd-agent:dd-agent $DD_AGENT_SSH"

run_command \
    "Setting SSH directory permissions (700)" \
    "sudo chmod 700 $DD_AGENT_SSH"

run_command \
    "Setting private key permissions (600)" \
    "sudo chmod 600 $PRIVATE_KEY"

# Summary
echo -e "${YELLOW}═══════════════════════════════════════════════════════════${NC}"
echo -e "${GREEN}✓ SSH configuration completed successfully!${NC}"
echo -e "${YELLOW}═══════════════════════════════════════════════════════════${NC}\n"

echo "Summary of executed operations:"
echo "  • SSH directory created: $DD_AGENT_SSH"
echo "  • Private key: $PRIVATE_KEY"
echo "  • Key converted to PEM format"
echo "  • known_hosts configured"
echo "  • Public key added to authorized_keys"
echo "  • Correct permissions applied"
echo ""
echo -e "${GREEN}Datadog Agent can now authenticate via SSH.${NC}\n"