ERROR (SSLError): SSL exception [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed : Cannot run Openstack command on the undercloud

Issue

source stackrc 后，openstack 命令失败，并显示：

ERROR (SSLError): SSL exception connecting to https://<undercloudip>:13000/v2.0/tokens: [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:579)

例如，对于 OSP16：

(undercloud) [stack@director ~]$ openstack baremetal node list
Failed to discover available identity versions when contacting https://10.226.36.11:13000. Attempting to parse version from URL.
Could not find versioned identity endpoints when attempting to authenticate. Please check that your auth_url is correct. SSL exception connecting to https://10.226.36.11:13000: HTTPSConnectionPool(host='10.226.36.11', port=13000): Max retries exceeded with url: / (Caused by SSLError(SSLError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:897)'),))

命令 getcert request ... 失败，并显示 Certificate at same location is already used by request with nickname