title: Upgrade Notes - Libcloud 0.6

## Upgrading from 0.5.x

### Changes

* SSL certificate verification is now enabled by default and an exception is
thrown if CA certificate files cannot be found.

To revert to the old behavior, set libcloud.security.VERIFY_SSL_CERT_STRICT
variable to False:

    ::python
    libcloud.security.VERIFY_SSL_CERT_STRICT=False

**Note: You are strongly discouraged from disabling SSL certificate validation.
If you disable it and no CA certificates files are found on the system you are
vulnerable to a man-in-the-middle attack**

Wiki page which describes how to install CA certificates on different operating systems can be found at [http://wiki.apache.org/incubator/LibcloudSSL](http://wiki.apache.org/incubator/LibcloudSSL).

* OpenStack driver now defaults to using OpenStack 1.1 API.

To preserve the old behavior and use OpenStack 1.0 API, pass
`api_version='1.0'` keyword argument to the driver constructor.

For example:

    ::python
    Cls = get_provider(Provider.OPENSTACK)
    driver = Cls('user_name', 'api_key', False, 'host', 8774, api_version='1.0')

* OpenNebula driver now defaults to using OpenNebula 3.0 API

To preserve the old behavior and use OpenNebula 1.4 API, pass
`api_version='1.4'` keyword argument to the driver constructor.

For example:

    ::python
    Cls = get_provider(Provider.OPENNEBULA)
    driver = Cls('key', 'secret', api_version='1.4')

For a whole list of the changes, please refer to the [Changelog](https://svn.apache.org/viewvc/libcloud/trunk/CHANGES?revision=1198753&view=markup).