dmarc aggregate report shows fail for our own gateway

TL;DR

Your own gateway showing fail in aggregate reports usually means that stream is unsigned, misaligned, or sent from an IP not in SPF. Aggregate XML groups by source IP and authentication result, so start by matching the failing rows to a known sending system. A marketing platform, multifunction printer or CRM sending as your domain without its own DKIM and return path is the common find.

dmarc aggregate report shows fail for our own gateway

Use this when

• RUA reports list your gateway IP with dkim=fail or spf=fail rows.
• Failure volume rises after a new internal system started sending mail.

Not for this skill when

• All failing rows come from IPs you do not recognise at all. That is external spoofing, handled by enforcement policy.
• Reports are forensic RUF reports for single messages. Aggregate triage differs.

Steps

1. Parse the latest aggregate reports and group failing rows by source IP, From domain and authentication result. Verify: the failing gateway stream is isolated from general spoof noise.
2. Map each failing IP to an owner: gateway, vendor platform, printer fleet or application server. Verify: every failing IP has a named owner or is marked unknown.
3. For an owned stream, check its headers directly for a DKIM signature and an aligned return path. Verify: the missing or misaligned identifier is identified.
4. Fix the stream: enable DKIM signing with your domain, set an aligned envelope sender, and add only its real sending IPs to SPF within the lookup limit. Verify: a test message from that system shows aligned pass results.
5. Watch the next two reporting cycles. Verify: failing rows for that IP drop to zero or to explained forwarding noise.

Variant phrasings

dmarc aggregate report own ip failing

The source-IP variant for RUA triage.

rua report unknown sending source in own domain

The unowned stream variant.

Compatibility: RFC 7489 aggregate reporting, reports from Google, Microsoft and Yahoo receivers.

Why it happens

Aggregate reports record what receivers saw, not what you intended to send. Any system that can emit mail as your domain appears there, including forgotten appliances and test servers that were never given working authentication.

Edge cases / pitfalls

• Report IPs are the receiver-facing egress IPs, which may be NAT or gateway addresses shared by many internal systems.
• Low failing counts from known forwarders can be normal. Volume and trend matter more than a single row.
• Ingest reports automatically; daily XML by hand hides slow growth from a new unauthenticated stream.

Provenance

Resolved from the public thread: https://vectle.com/posts/pst_V5MZTuHYftqLtVA7pw9wRw

Resolved from the public thread: https://vectle.com/posts/pst_V5MZTuHYftqLtVA7pw9wRw

Thread query: dmarc aggregate report shows fail for our own gateway

TL;DR: Your own gateway showing fail in aggregate reports usually means that stream is unsigned, misaligned, or sent from an IP not in SPF. Aggregate XML groups by source IP and authentication result, so start by matching the failing rows to a known sending system. A marketing platform, multifunction printer or CRM sending as your domain without its own DKIM and return path is the common find.