When pointing a root domain (@ record) to an Azure cloud service (*.cloudapp.net), we encounter RFC compliance issues with CNAME records at the zone apex. Here's the technical breakdown:

# Typical CNAME configuration that WON'T work for root domain
mydomain.com.    IN  CNAME   mymachine.cloudapp.net.
www.mydomain.com. IN CNAME   mymachine.cloudapp.net.

DNS RFC 1912 and RFC 2181 prohibit CNAME records at the zone apex (@) because:

• CNAME can't coexist with other records (MX, NS, TXT)
• Root domain must resolve to A/AAAA records for email delivery
• DNS resolution would require multiple lookups

Option 1: Use Azure DNS ALIAS Records

If you can transfer DNS to Azure:

# Azure CLI example to create alias record
az network dns record-set cname set-record \
  --resource-group myResourceGroup \
  --zone-name mydomain.com \
  --record-set-name "@" \
  --cname mymachine.cloudapp.net \
  --alias true

Option 2: GoDaddy A Record Workaround

1. Resolve your Azure endpoint IP dynamically:

#!/bin/bash
# Script to update GoDaddy A record
NEW_IP=$(dig +short mymachine.cloudapp.net | grep -E '^[0-9.]+$' | head -1)
curl -X PUT "https://api.godaddy.com/v1/domains/mydomain.com/records/A/@" \
  -H "Authorization: sso-key ${GODADDY_KEY}:${GODADDY_SECRET}" \
  -H "Content-Type: application/json" \
  -d "[{\"data\": \"${NEW_IP}\", \"ttl\": 600}]"

Option 3: DNS Provider with CNAME Flattening

Services like Cloudflare support this natively:

# Cloudflare API example
curl -X PATCH "https://api.cloudflare.com/client/v4/zones/:zone_id/dns_records/:record_id" \
  -H "Authorization: Bearer $TOKEN" \
  -H "Content-Type:application/json" \
  -d '{"type":"CNAME","name":"@","content":"mymachine.cloudapp.net","proxied":false}'

• For Azure, consider using Azure Front Door with custom domains
• Implement DNS TTL values under 300 seconds for faster failover
• Set up monitoring for IP changes with Azure Event Grid

When hosting a website on Azure VMs (*.cloudapp.net) with GoDaddy DNS, many developers encounter this specific roadblock:

Error: "A record of a different type exists for the hostname @, could not create CNAME"

This occurs because:

• RFC standards prohibit CNAME records at the root domain level (@) when other record types exist
• GoDaddy's DNS interface enforces this restriction more strictly than some other providers
• Azure's dynamic VIP assignments make A records problematic for long-term stability

Option 1: Use GoDaddy Forwarding

GoDaddy provides domain forwarding that can mask the CNAME limitation:

1. Navigate to Domain Settings > Forwarding
2. Set "mydomain.com" to forward to "www.mydomain.com" (301 redirect)
3. Create CNAME for www pointing to your Azure VM hostname

Option 2: DNS Provider Workaround

Some DNS providers support ALIAS/ANAME records that function like CNAMEs at root:

; Cloudflare example
@    IN    ANAME    mymachine.cloudapp.net.
www  IN    CNAME    mymachine.cloudapp.net.

Option 3: Azure DNS Zone Delegation

For production environments, consider delegating DNS to Azure:

# Azure CLI command to create DNS zone
az network dns zone create \
  --name mydomain.com \
  --resource-group MyResourceGroup

If you must use A records, implement automatic updates:

# PowerShell script to update GoDaddy DNS
$headers = @{
  "Authorization" = "sso-key $($apiKey):$($apiSecret)"
}
$body = @{
  data = (Resolve-DnsName mymachine.cloudapp.net).IPAddress
} | ConvertTo-Json
Invoke-RestMethod -Method Put -Uri "https://api.godaddy.com/v1/domains/mydomain.com/records/A/@" -Body $body -Headers $headers

For production sites, we recommend:

• Using Azure App Service with custom domains instead of raw VMs
• Implementing Azure Front Door for global traffic routing
• Migrating DNS to Azure DNS or Cloudflare for modern record support