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# DKIM Record Publishing — Cloudflare

## Problem

OpenDKIM on Hetzner was signing outbound mail for all 21 client domains correctly (private keys generated, milter running, signatures added to every message) — but the **public keys were never published to DNS**. This caused Gmail/other recipients to fail DKIM verification, drop the spam score, and quarantine the mail.

**Symptom:** Wordfence alerts (and other transactional email from Kaburu sites) consistently flagged as spam in Gmail.

## Root Cause

CyberPanel's email installer generates DKIM keys locally and configures OpenDKIM, but does **not** publish the public key TXT records to Cloudflare. The records at `default._domainkey.<domain>` were either missing or contained the wrong (empty/stale) value.

## Fix Applied (2026-07-30)

Published `default._domainkey.<domain>` TXT records for all 21 Kaburu domains:

- 24hrresponse.com
- aberdeenrda.co.uk
- bankhousecatering.co.uk
- claybusters.scot
- dm-ph.com
- doctorfin.co.uk
- friendscic.org
- ggsgenerators.co.uk
- jafricasafari.com
- kaburu.cc, kaburu.co, kaburu.co.uk
- kaburusvr.uk
- l8waterhygiene.co.uk
- longniddrybowlingclub.com, .co.uk
- myretonmarquees.co.uk
- pilates-edinburgh.co.uk
- thechippyvan.co.uk
- touchwell.co.uk
- womenunlimited.africa

## Verification

```bash
dig TXT default._domainkey.24hrresponse.com +short
# Should return: "v=DKIM1; h=sha256; k=rsa; p=MIIBIjA..."

ssh root@kaburusvr 'tail -20 /var/log/mail.log | grep opendkim'
# Should show: "DKIM-Signature field added (s=default, d=24hrresponse.com)"
```

## Re-running the Publish Script

Located at: `/root/publish-dkim.sh` on kaburusvr (Hetzner)

What it does:
1. Reads CF token from `/root/.secrets/cloudflare`
2. Lists all zones in the Cloudflare account
3. For each domain in `/etc/opendkim/keys/`:
   - Extracts the public key from `default.txt`
   - Looks up the zone ID
   - Creates or updates the `default._domainkey.<domain>` TXT record

When to re-run:
- A new domain is added to the Hetzner server
- DKIM keys are regenerated (e.g. by CyberPanel reinstall)
- A new site is migrated to the server
- DNS records need rotation (every 6-12 months for hygiene)

## Gotchas

- **`grep -F "^domain|"` doesn't work** — `^` with `-F` treats `|` as literal. Use `awk -F'|' '$1 == d'` instead. Caught on first run.
- The script lives on Hetzner because it needs the CF token from `/root/.secrets/cloudflare` and the OpenDKIM keys from `/etc/opendkim/keys/`. Don't move it elsewhere.
- DNS propagation: Cloudflare typically serves new records within 1-5 minutes. No need to wait for TTL.
- DNSSEC warning ("key not secure") from `opendkim-testkey` is informational only, doesn't block signing.

## Related

- [[opnsense]] — OPNsense firewall (separate email chain, Brevo SMTP fallback)
- Wiki: `wiki/infrastructure/opnsense.md` — Unbound/DNS notes
- Wiki: `wiki/web/cyberpanel.md` — CyberPanel-specific email setup

## Verification log (2026-07-30)

Before fix:
```
$ dig TXT default._domainkey.24hrresponse.com +short
# (empty)
```

After fix:
```
$ dig TXT default._domainkey.24hrresponse.com +short
"v=DKIM1; h=sha256; k=rsa; p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAi6SuVjoBZaUmtPVD+p6Nel23K5gFpJHfHR5hlM8r73AVjmC7toVZKblrIob0RFhe8xcT1IYS3vE0IECxV8oOlBSEFgKGVPkBvKt9gh3AqvG+LB8yeVOho7lypFScRZiENBE3GO+/Rj3wCjPq19BUn87TsNfB3EHO9IPjUykFACO91nUns0QwJkL..." "W5hu71HjOcExh+qNOumDpE1"
```

Op en DKIM log confirmed signing active throughout:
```
2026-07-30T18:36:28 opendkim[1538]: 7AE90C5D26: DKIM-Signature field added (s=default, d=24hrresponse.com)
... (5 more 24hrresponse.com entries from active brute-force block alerts)
```