DMARC レコード生成

メール認証用の DMARC TXT レコードを、ポリシー、レポート先、アラインメント、適用率から作成します。

DMARC 設定

ドメイン

Policy (p)Subdomain policy (sp)

Rollout percentage (pct): 100%Aggregate report emails (rua)

dmarc@example.com

Forensic report emails (ruf)

DKIM alignment (adkim)SPF alignment (aspf)

Failure options (fo)Report interval seconds (ri)

DNS record typeTXT

Host nameTXT value

v=DMARC1; p=none; rua=mailto:dmarc@example.com; adkim=r; aspf=r; fo=1

Record length69

Report URIs1

Enforcement監視

Domain is ready

Publish this TXT record at the _dmarc host for the domain.

Aggregate reporting enabled

rua reports help you monitor legitimate and failing email sources.

Start with monitoring

p=none is safest while you validate SPF, DKIM, and legitimate senders.

TXT length is OK

The record is within the common 255-character DNS TXT string limit.

1. Monitor

Use p=none and collect rua reports until all legitimate senders are known.

2. Quarantine

Apply quarantine to a small pct first, then increase as failures are resolved.

3. Reject

Move to reject after SPF/DKIM alignment is stable and reports look clean.