Add note on some drivers not supporting "proxy_url" constructor argument.
@@ -76,6 +76,18 @@ With basic auth authentication (http proxy):
2. Passing ``proxy_url`` argument to the connection class constructor
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+. note::
+
+ Some drivers don't correctly pass ``proxy_url`` argument to the connection
+ class and don't support ``proxy_url`` constructor argument.
+
+ If you pass this argument to the driver constructor, but it doesn't appear
+ to be working, it's likely the driver doesn't support this method.
+
+ In such scenarios, you are advised to use some other method of setting a
+ proxy (e.g. by setting an environment variable or by using
+ :meth:`libcloud.common.base.LibcloudConnection.set_http_proxy` method).
+
By passing ``proxy_url`` argument to the
:class:`libcloud.common.base.Connection` class constructor, you can specify
which proxy to use for a particular connection.
