On Thu, Jan 07, 2021 at 05:10:29PM -0800, Quanah Gibson-Mount wrote: > Using wireshark, we can see the following signature algorithms are offered > from the client side (which uses TLSv1.2) for both the working and failing > servers: > > 0x0403 ECDSA-SHA256 > 0x0503 ECDSA-SHA384 > 0x0603 ECDSA-SHA512 > 0x0401 RSA-SHA256 > 0x0501 RSA-SHA384 > 0x0601 RSA-SHA512 > 0x0402 DSA-SHA256 > 0x0203 ECDSA-SHA1 > 0x0201 RSA-SHA1 > 0x0202 DSA-SHA1 You're leaving out too much detail. Post the full client hello decoded by "tshark": https://www.spinics.net/lists/openssl-users/msg05623.html > If I test connecting on the command line to the server in question, I can > connect using any of RSA+SHA256, RSA+SHA384, and RSA+SHA512 from the above > signature algorithms without issue, like: What sort of certificate does the server have. Are there any ssl module settings in its openssl.cnf file? -- Viktor.