Node.js dns Module Guide

The dns module provides DNS resolution and lookup capabilities. Here's how to use it for network operations.

Best Practices#

Lookup vs Resolve:
✓ lookup() uses OS resolver (cached)
✓ resolve() queries DNS directly
✓ Use lookup() for general use
✓ Use resolve() for specific records

Performance:
✓ Cache DNS results
✓ Use connection pooling
✓ Set reasonable timeouts
✓ Handle failures gracefully

Error Handling:
✓ Check error.code
✓ Implement retries
✓ Log DNS failures
✓ Have fallback servers

Avoid:
✗ Hardcoding IPs
✗ Ignoring TTLs
✗ Blocking on DNS
✗ No timeout handling

The Node.js dns module provides comprehensive DNS resolution capabilities. Use lookup() for general hostname resolution with OS caching, and resolve*() methods for specific record types. Implement caching for performance, handle errors with retry logic, and use custom resolvers for specific DNS servers. The promises API makes async DNS operations clean and composable for modern Node.js applications.

Node.js dns Module Guide

Basic Lookup#

Promise-based API#

Lookup Options#

Resolve DNS Records#

SOA Records#

SRV Records#

Reverse DNS Lookup#

Resolve Any Record Type#

Custom DNS Servers#

DNS Cache#

Health Check with DNS#

Error Handling#

Best Practices#

Conclusion#

Share this article

Related articles

Node.js DNS Module Guide

Node.js HTTP Module Deep Dive

Node.js Net Module Guide