/dev/random any good in AWS EC2 for use in making a shared key that will be passed over a secure channel? i am concerned that a launched instance would have not much entropy to begin with. what if i delay using it for a couple minutes to get random EBS delays for more entropy?
i will not be logging in to these instances. one instance will generate a key and place it (in hex) in a tag. another instance will get the key from that tag and set up a VPN between them. maybe there is a way to use PKC for this although the path to/from tags is https, which AWS depends on for login passwords.
i guess timing to access the EC2 API can be another source of entropy.