DKIM failures and SPF questions

[Knute Johnson]

I have sendmail 8.17.1.9 running my personal email accounts. I have set
up DKIM and have specified a DMARC record in my DNS. I have that
configured to send me status emails. My question is why I have so many
failures. The message I get often show failures of DKIM but SPF passes.
There is no explanation why they failed. In the _dmarc record I have
p=quarantine and ptc=100. My SPF record specifies -all.

The failure rate is probably 20% on DKIM and hardly ever on SPF. Do I
need to look for something here?

Thanks,

[HQuest]

First and foremost, not sponsored. Those are a few tools I've found out there that helped me troubleshoot these and other problems myself.

https://dkimvalidator.com/
https://easydmarc.com/tools/
https://dmarcian.com/domain-checker/

This might give you some hints on where to look next.

[Marco Moock]

Post by Knute Johnson
I have sendmail 8.17.1.9 running my personal email accounts. I have
set up DKIM and have specified a DMARC record in my DNS. I have that
configured to send me status emails. My question is why I have so
many failures.

Set up another test server that checks DKIM, SPF and DMARC and check
what those tools report in the logs.

[none]

I have sendmail 8.17.1.9 running my personal email accounts.  I have set
up DKIM and have specified a DMARC record in my DNS.  I have that
configured to send me status emails.  My question is why I have so many
failures.  The message I get often show failures of DKIM but SPF passes.
 There is no explanation why they failed.  In the _dmarc record I have
p=quarantine and ptc=100.  My SPF record specifies -all.
The failure rate is probably 20% on DKIM and hardly ever on SPF.  Do I
need to look for something here?
Thanks,

I have also 20% failing, most of this is outlook.com/sendgrid. Seems to
be known