docker error: x509: certificate signed by unknown

Question

while running docker commands, I keep getting such error:

$ sudo docker search mattdm/fedora
2014/06/05 22:12:25 Error: Get https://index.docker.io/v1/search?q=mattdm%2Ffedora: x509: certificate signed by unknown authority

I'm using Fedora 20 x86_64 without any http proxy.

I searched with google, but failed to find any clue of this, and have no idea how to troubleshoot this error, could anyone give me some prompt on fixing this?

here is some additional info may help:

$ sudo docker version
Client version: 0.11.1
Client API version: 1.11
Go version (client): go1.2.1
Git commit (client): fb99f99/0.11.1
Server version: 0.11.1
Server API version: 1.11
Git commit (server): fb99f99/0.11.1
Go version (server): go1.2.1

$ curl https://index.docker.io/v1/search?q=mattdm/fedora
{"query": "mattdm/fedora", "num_results": 2, "results": [{"is_trusted": false, "is_official": false, "name": "mattdm/fedora", "star_count": 49, "description": "A basic Fedora image corresponding roughly to a minimal install, minus some things which don't make sense in a container. Use tag `f20` for Fedora 20 or `f19` for Fedora 19."}, {"is_trusted": false, "is_official": false, "name": "mattdm/fedora-small", "star_count": 8, "description": "A small Fedora image on which to build. Contains just enough that you'll be able to run `yum install` in your dockerfiles to create something useful. Use tag `f19` for Fedora 19."}]}

$ ls -l  /etc/pki/tls/certs/
total 1500
lrwxrwxrwx. 1 root root     49 Feb 18 03:58 ca-bundle.crt -> /etc/pki/ca-trust/extracted/pem/tls-ca-bundle.pem
-rw-r--r--. 1 root root 713687 Jan  5  2013 ca-bundle.crt.rpmsave
lrwxrwxrwx. 1 root root     55 Feb 18 03:58 ca-bundle.trust.crt -> /etc/pki/ca-trust/extracted/openssl/ca-bundle.trust.crt
-rw-r--r--. 1 root root 796502 Jan  5  2013 ca-bundle.trust.crt.rpmsave
-rw-r--r--. 1 root root   1338 Mar 14 12:13 ca-certificates.crt
-rw-------. 1 root root   1025 Sep 25  2012 localhost.crt
-rwxr-xr-x. 1 root root    610 Apr  8 08:36 make-dummy-cert
-rw-r--r--. 1 root root   2242 Apr  8 08:36 Makefile
-rwxr-xr-x. 1 root root    829 Apr  8 08:36 renew-dummy-cert

Answer 1

This was proved to be related to the CDN provider.

check here: https://github.com/dotcloud/docker/issues/6474