From: Robert Moskowitz <rgm at htt-consult.com> > Does the version of OpenSSL on Centos 6.5 support ECDSA keypairs? Google finds: "ECDSA Support in OpenSSL Elliptic Curve Digital Signature Algorithm (ECDSA) is a variant of the Digital Signature Algorithm (DSA) which uses Elliptic Curve Cryptography (ECC). Note that only the nistp256 and nistp384 curves are supported." https://access.redhat.com/site/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/6.5_Release_Notes/bh-chap-security.html JD