Should "record not found" errors from opendkim for external domains be showing up in /var/log/mail.err?

I have set up opendkim for the first time. I see many of log entries similar to the following in my /var/log/mail.err file:

Oct 13 20:02:51 email opendkim[24304]: 0873142234: key retrieval failed (s=omega, d=ctdems.org): 'omega._domainkey.ctdems.org' record not found

Presumably, these are generated when my opendkim software checks the signatures on incoming mail and is unable to check the signatures because it can't find the appropriate TXT record in DNS.

I'm not entirely sure whether these "errors" are anything to be worried about or if anything should or could be done about them. But being new to opendkim, I'm not entirely sure. The fact that they are showing up in the mail.err file has me wondering.

Are these errors "normal" and should they be moved to another log file?

Solution 1:

Presumably, these are generated when my opendkim software checks the signatures on incoming mail and is unable to check the signatures because it can't find the appropriate TXT record in DNS.

Exactly.

These are ordinary informational log messages that require no administrator intervention. I would argue that these messages should not be logged with priority ‘error’, but that is the OpenDKIM developers’ decision.