cwagent.json.tftpl

#!/usr/bin/env bash

CWAGENT_CONFIG_DIR="/opt/aws/amazon-cloudwatch-agent/etc"
CWAGENT_CONFIG_FILE="$CWAGENT_CONFIG_DIR/amazon-cloudwatch-agent.json"

# Check if parent directory exists and is writable
if [ ! -d $CWAGENT_CONFIG_DIR ] || [ ! -w $CWAGENT_CONFIG_DIR ]; then
    echo "Error: Directory $CWAGENT_CONFIG_DIR does not exist or is not writable"
    exit 1
fi

# Configuration that aims to report most metrics as provided for managed NAT Gateways.
#
# Adapted from the fck-nat project. All credit goes to its original contributors.
# Original documentation: https://fck-nat.dev/develop/features/#metrics
cat <<EOF > $CWAGENT_CONFIG_FILE
{
  "agent": {
    "metrics_collection_interval": 60,
    "run_as_user": "root",
    "usage_data": false
  },
  "metrics": {
    "namespace": "${cloudwatch_namespace}",
    "metrics_collected": {
      "net": {
        "resources": ${cloudwatch_interfaces},
        "measurement": [
          { "name": "bytes_recv", "rename": "BytesIn",  "unit": "Bytes" },
          { "name": "bytes_sent", "rename": "BytesOut",  "unit": "Bytes" },
          { "name": "packets_sent", "rename": "PacketsOutCount",  "unit": "Count" },
          { "name": "packets_recv", "rename": "PacketsInCount",  "unit": "Count" },
          { "name": "drop_in", "rename": "PacketsDropInCount",  "unit": "Count" },
          { "name": "drop_out", "rename": "PacketsDropOutCount",  "unit": "Count" }
        ]
      },
      "netstat": {
        "measurement": [
          { "name": "tcp_syn_sent", "rename": "ConnectionAttemptOutCount",  "unit": "Count" },
          { "name": "tcp_syn_recv", "rename": "ConnectionAttemptInCount",  "unit": "Count" },
          { "name": "tcp_established", "rename": "ConnectionEstablishedCount",  "unit": "Count" }
        ]
      },
      "ethtool": {
        "interface_include": ${cloudwatch_interfaces},
        "metrics_include": [
          "bw_in_allowance_exceeded",
          "bw_out_allowance_exceeded",
          "conntrack_allowance_exceeded",
          "pps_allowance_exceeded"
        ]
      },
      "mem": {
        "measurement": [
          { "name": "used_percent", "rename": "MemoryUsed",  "unit": "Percent" }
        ]
      }
    },
    "append_dimensions": {
      "InstanceId": "\$${aws:InstanceId}",
      "AutoScalingGroupName": "\$${aws:AutoScalingGroupName}"
    }
  }
}
EOF

systemctl restart amazon-cloudwatch-agent