I hope the statement above does not mean that it is not possible to
designate a VPC and a given Security Group for a given machine
instance.
It means that (as per the Amazon docs, too [1]), you cannot assign a
VPC and a security group *name* ("old-style" security groups) at the
same time.
You *can*, however, assign a VPC and a security group *ID*
("VPC-style" security groups).
ap
[1]
http://docs.aws.amazon.com/AWSEC2/latest/APIReference/ApiReference-query-RunInstances.html, look for
"SecurityGroup.n"
