We've recently implemented DKIM for automated emails sent out from our website (SMTP on static IP). However we cannot implement DKIM for our hosted exchange email accounts (managed hosting sends from a range of IPs).
So in the DMARC reports I'm getting passes for emails sent from our website via SMTP but fails for emails sent via the individual exchange user accounts. SPF is also implemented and that passes for both.
As far as I can manage to find on the web this should not hurt our reputation but I'm keen to double check this as I'm not 100% certain our DMARC setting is Ok:
v=DMARC1; p=none; rua=mailto:webmaster@mydomain.co.uk; pct=100
Example DMARC result:
<record>
<row>
<source_ip>IPADDRESS OMMITTED</source_ip>
<count>1</count>
<policy_evaluated>
<disposition>none</disposition>
<dkim>fail</dkim>
<spf>pass</spf>
</policy_evaluated>
</row>
<identifiers>
<header_from>mydomain.com</header_from>
</identifiers>
<auth_results>
<spf>
<domain>mydomain.com</domain>
<result>pass</result>
</spf>
</auth_results>
</record>
Any input most appreciated, Thanks