# Fix email authentication for amazon.com

You are working on the DNS and mail configuration for amazon.com.
Measured by MailAuthWatch on 17 Oct 2026 from public DNS. Grade A (90/100).
Report: https://www.mailauthwatch.com/check/amazon.com

## What is published right now (do not assume anything else)
- SPF (TXT amazon.com): v=spf1 include:spf1.amazon.com include:spf2.amazon.com include:amazonses.com -all   — valid, 4 of 10 lookups
- DMARC (TXT _dmarc.amazon.com): v=DMARC1;p=quarantine;pct=100;rua=mailto:report@dmarc.amazon.com;ruf=mailto:report@dmarc.amazon.com
- DKIM: m1._domainkey (1024-bit)
- MX: amazon-smtp.amazon.com  → a custom mail host
- Nameservers: ns-1447.awsdns-52.org, ns-1707.awsdns-21.co.uk …  → records are managed in Amazon Route 53

## Tasks, in order of impact
### 1. One DKIM key is 1024-bit.
Why: Selector m1._domainkey is under 2048 bits, which some receivers already downgrade. 
Rotate to a 2048-bit key at the sending service.

## Rules
- Publish exactly one SPF record; never add a second v=spf1 TXT.
- Do not remove any include: or ip4: you cannot account for; mail may depend on it.
- Do not set DMARC to p=reject in one step; stage through p=none → quarantine → reject.
- Show the planned DNS changes as a diff (record, old value, new value) before applying them.
- If you cannot access Amazon Route 53, stop and say exactly what access you need.

## Verify
  dig +short TXT amazon.com
  dig +short TXT _dmarc.amazon.com
Then open https://www.mailauthwatch.com/check/amazon.com?fresh=1 and confirm:
  the grade is unchanged and no new issues appear. Target grade: A.

## Report back
List each record you changed (name, type, old value, new value), what you verified, and anything you could not do.