dns_record_audit.sh

#!/usr/bin/env bash

set -euo pipefail

# dns_record_audit.sh
# Audits DNS records (A, AAAA, MX, NS, TXT, CNAME) for domains from a file.

usage() {
  cat <<'EOF'
Usage: ./dns_record_audit.sh --input domains.txt [options]

Options:
  --input FILE           Domain list file (required)
  --server NS            Query specific DNS server (optional)
  --types LIST           Comma-separated types (default: A,AAAA,MX,NS,TXT,CNAME)
  --timeout SECONDS      dig timeout (default: 3)
  -h, --help             Show help
EOF
}

INPUT_FILE=""
SERVER=""
TYPES="A,AAAA,MX,NS,TXT,CNAME"
TIMEOUT=3

while [[ $# -gt 0 ]]; do
  case "$1" in
    --input) INPUT_FILE="$2"; shift 2 ;;
    --server) SERVER="$2"; shift 2 ;;
    --types) TYPES="$2"; shift 2 ;;
    --timeout) TIMEOUT="$2"; shift 2 ;;
    -h|--help) usage; exit 0 ;;
    *) echo "Unknown option: $1"; usage; exit 1 ;;
  esac
done

if [[ -z "$INPUT_FILE" || ! -f "$INPUT_FILE" ]]; then
  echo "Missing input file: $INPUT_FILE"
  exit 1
fi

IFS=',' read -r -a type_array <<< "$TYPES"

while IFS= read -r domain; do
  [[ -z "$domain" || "$domain" =~ ^# ]] && continue
  echo "=== $domain ==="
  for record_type in "${type_array[@]}"; do
    if [[ -n "$SERVER" ]]; then
      result="$(dig +time="$TIMEOUT" +tries=1 +short "$domain" "$record_type" @"$SERVER" | paste -sd ';' -)"
    else
      result="$(dig +time="$TIMEOUT" +tries=1 +short "$domain" "$record_type" | paste -sd ';' -)"
    fi
    if [[ -z "$result" ]]; then
      result="NO_RECORD"
    fi
    printf "%-6s %s\n" "$record_type" "$result"
  done
  echo
done < "$INPUT_FILE"