docker login fails: tls: server selected unsupported protocol version 301

Question

I am using docker version 18.09.0, build 4d60db4 in a Windows machine and I am trying to login to Artifactory using the following command,

docker login docker-registery.company.net

It prompts for username and password and I am providing them, however I am not able to login. It gives me the following error:

Error response from daemon: Get https://docker-registery.company.net/v2/: tls: server selected unsupported protocol version 301

Note: I am able to login to the Artifactory Repo Browser through my web browser by using the same username and password.

What is causing this issue when I try to login from the command-line? Is it some kind of proxy or certificate issue?

Answer 1

protocol version 301 = TLS 1.0 - that is insecure TLS version, which has been selected by the server (in theory by Artifactory, but there can be reverse proxy, Tomcat, etc. where TLS can be configured as well).

Configure properly TLS on the server side (enable support for TLS 1.1+) and your docker client will be able to establish a secure TLS connection. "insecure registry" is just insecure workaround.