On 18 Feb 2011, at 09:09, Tena Sakai wrote:
> I had created a security group "intra." I opened ssh port from 0 to
> 65535, and launched instances (I unleashed 2 at a time in a same
> geography zone) each belonging to the group intra. So, here, ssh
> is a security rule of a security group intra. A field for each
> rule is "source." I had different settings for the source field,
> but what I had been failing to do is to have this field known by
> the name of the group, namely intra. By doing so, each instance
> that belongs to this group can get to each other.
I'm glad you got to the bottom of the problem, I've never fully understood the EC2 "Security Groups" but I found that the default group was adequate and I didn't need to create my own. Now that I look at it more closely it appears to open all incoming ports to the local instances and incoming port 22 to the world which would agree with I've seen.
> Many thanks for your guidance all along. In a week or two, I look
> forward to put together a mini "how-to openMPI on cloud".
If you do this I would appreciate the chance to proof-read it before you go public, I have many thousands of hours of EC2 time to my name and have spent much of it configuring and testing MPI librarys within them to allow me to test my debugger which sits on top of them.
Ashley Pittman, Bath, UK.
Padb - A parallel job inspection tool for cluster computing