sendmail: dh key too small

Solution Verified - Updated -


After updating openssl libraries, sendmail is not able to make connections to external server:

sendmail[123]: STARTTLS=client: 645:error:14082174:SSL routines:SSL3_CHECK_CERT_AND_ALGORITHM:dh key too small:s3_clnt.c:2429:

and the message is not delivered.


  • Red Hat Enterprise Linux
  • sendmail
  • openssl

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