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Jason CrawfordFlag for United States of America

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DKIM Setup

I have setup DKIM for my custom domain in Exchange Online and it shows pass when sending a test email and inspecting the headers:

ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass
 smtp.mailfrom=mydomain.net; dmarc=pass action=none
 header.from=mydomain.net; dkim=pass header.d=mydomain.net; arc=none
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed;
 d=mydomain.onmicrosoft.com; s=selector2-mydomain-onmicrosoft-com;
 h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck;
 bh=DelGf+gWPEhOvltwPFOouDoJUz05MJ7aNGn/c7H8Dro=;
 b=FF7o+GdJEn3iwuwslLI+FzxA8zlUPoVwwvRHIEbQpIrmOc5tPOtAjKYR6E8OD1ZEqJ7aj7q2Qpw4DZPFm8i5iTg/WLwv9vWBTW/2Z8haVXJ9OuJLCdZ91pLscP36byQPzDJ4QPIoWQlCRqrjwyawoBiz0c5YWAmOp321GU0LLh8=

My question is this, I have an application sending email as mydomain.net using IIS SMTP and I have accounted for this IP in my SPF record so it looks something like this:

v=spf1 ip4:1.2.3.4 include:spf.protection.outlook.com -all

If email is sent from 1.2.3.4 for mydomain.net will it still pass DKIM?  How do I account for that IP in my DKIM setup?
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M A
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-->If email is sent from 1.2.3.4 for mydomain.net will it still pass DKIM?  How do I account for that IP in my DKIM setup?
Your IP will be checked in SPF not in DKIM.

For DKIM singing receiving server will not check your IP. It will check the DKIM signing and your DNS records.
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ASKER

Thank you for the response.  If 1.2.3.4 is not relaying through Exchange Online and sending directly to the internet as mydomain.net, will DKIM still pass?
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1) SPF != DKIM

No SPF DNS changes will effect DKIM signing or verification.

No DKIM DNS changes will effect SPF authorization checks.

2) As MAS said.

"If 1.2.3.4 is not relaying through Exchange Online and sending directly to the internet as mydomain.net, will DKIM still pass?"

No.

If you have your DKIM DNS records setup correctly + you DKIM signing setup correctly (usually OpenDKIM or rspamd) then messages must be sent through your DKIM signing server before submission to any Mailbox Provider (Google/Yahoo/etc...) so you can't "send directly to the Internet" ever. You must route all message through your DKIM signing server.