# Fix email authentication for uber.com

You are working on the DNS and mail configuration for uber.com.
Measured by MailAuthWatch on 17 Oct 2026 from public DNS. Grade A (95/100).
Report: https://www.mailauthwatch.com/check/uber.com

## What is published right now (do not assume anything else)
- SPF (TXT uber.com): v=spf1 include:uber.com._nspf.vali.email include:%{i}._ip.%{h}._ehlo.%{d}._spf.vali.email include:mailgun.org ~all   — valid, 7 of 10 lookups
- DMARC (TXT _dmarc.uber.com): v=DMARC1; p=quarantine; rua=mailto:dmarc_agg@vali.email
- DKIM: google._domainkey (1024-bit), k1._domainkey (1024-bit), k2._domainkey (2048-bit), k3._domainkey (2048-bit), s1._domainkey (2048-bit), s2._domainkey (1024-bit), smtp._domainkey (1024-bit), mandrill._domainkey (1024-bit), hs1._domainkey (2048-bit), zendesk1._domainkey (2048-bit), zendesk2._domainkey (2048-bit), mte1._domainkey (2048-bit), mte2._domainkey (2048-bit), m1._domainkey (1024-bit), smtpapi._domainkey (1024-bit)
- MX: aspmx.l.google.com, alt1.aspmx.l.google.com, alt2.aspmx.l.google.com, alt3.aspmx.l.google.com, alt4.aspmx.l.google.com  → Google Workspace
- Nameservers: edns126.ultradns.biz, edns126.ultradns.com …  → DNS host not recognised

## Tasks, in order of impact
### 1. 7 DKIM keys are 1024-bit.
Why: Selectors google._domainkey, k1._domainkey, s2._domainkey, smtp._domainkey, mandrill._domainkey, m1._domainkey, smtpapi._domainkey are 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 the DNS provider or Google Workspace, stop and say exactly what access you need.

## Verify
  dig +short TXT uber.com
  dig +short TXT _dmarc.uber.com
Then open https://www.mailauthwatch.com/check/uber.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.