DNS Setup

You are a DNS administrator. The user wants to configure DNS records for a domain.

What to check first

• Verify you have access to your domain registrar's DNS management panel (GoDaddy, Namecheap, AWS Route 53, etc.)
• Confirm your nameservers are pointing to your DNS provider if switching providers
• Check current DNS records with dig yourdomain.com @8.8.8.8 or nslookup yourdomain.com

Steps

1. Log into your DNS provider's control panel and navigate to the DNS records or zone file section
2. Identify the record type needed: A (IPv4), AAAA (IPv6), CNAME (alias), MX (mail), TXT (text/verification), NS (nameserver), or SOA (Start of Authority)
3. For an A record pointing to a web server, enter the hostname (e.g., example.com or www.example.com), select type "A", and enter your IPv4 address (e.g., 203.0.113.42)
4. For email setup, add an MX record with your domain name, priority level (lower number = higher priority, typically 10), and mail server address (e.g., mail.example.com)
5. For email authentication, create a TXT record for SPF with value v=spf1 include:_spf.google.com ~all (adjust provider as needed)
6. Add DKIM TXT records provided by your email service, typically named default._domainkey with the public key value
7. Add DMARC TXT record as _dmarc.example.com with policy like v=DMARC1; p=quarantine; rua=mailto:admin@example.com
8. Save all records and wait 15 minutes to 48 hours for DNS propagation, then verify with dig or online tools

Code

#!/bin/bash
# DNS configuration verification script

DOMAIN="$1"

if [ -z "$DOMAIN" ]; then
  echo "Usage: ./dns_check.sh yourdomain.com"
  exit 1
fi

echo "=== DNS Records for $DOMAIN ==="

echo -e "\n[A Records]"
dig +short A $DOMAIN @8.8.8.8

echo -e "\n[AAAA Records - IPv6]"
dig +short AAAA $DOMAIN @8.8.8.8

echo -e "\n[MX Records - Mail]"
dig +short MX $DOMAIN @8.8.8.8

echo -e "\n[TXT Records - SPF/DKIM/DMARC]"
dig +short TXT $DOMAIN @8.8.8.8
dig +short TXT default._domainkey.$DOMAIN @8.8.8.8
dig +short TXT _dmarc.$DOMAIN @8.8.8.8

Note: this example was truncated in the source. See the GitHub repo for the latest full version.

Common Pitfalls

• Treating this skill as a one-shot solution — most workflows need iteration and verification
• Skipping the verification steps — you don't know it worked until you measure
• Applying this skill without understanding the underlying problem — read the related docs first

When NOT to Use This Skill

• When a simpler manual approach would take less than 10 minutes
• On critical production systems without testing in staging first
• When you don't have permission or authorization to make these changes

How to Verify It Worked

• Run the verification steps documented above
• Compare the output against your expected baseline
• Check logs for any warnings or errors — silent failures are the worst kind

Production Considerations

• Test in staging before deploying to production
• Have a rollback plan — every change should be reversible
• Monitor the affected systems for at least 24 hours after the change