Hi All,
To start out what I'm trying to do is prototype an HPC computing cluster. Simplified it's a head node with one ethernet interface open to the outside world and the second NIC on a private network. There will be multiple compute nodes that have a single NIC on the private network. The compute nodes have two way access to the head node but only outgoing connections to the Internet.
In my case, once this is deployed all the nodes will still run inside vbox to provide a custom environment different than what's on the bare metal.
My confusion (well current point of confusion) is the networking. My prototype is being run on a University machine which only is allowed one IP address. It runs Scientific Linux 6.5 (a RHEL derivative similar to CentOS), I7-3770K, 32GB RAM, lots of disk. Vbox is version 4.3.16
We need outgoing Internet access for NTP and data transfers which I believe means NAT Networking. People what to connect from home so port forwarding is needed.
My first problem I cannot find a good explanation of the different choices for different virtual network types. I understand bridged and NAT networking but how is NAT different from NAT Networking and what exactly does internal network and host only allow/deny?
Second question is how to specify port forwarding. The documentation I've read says I should be able to leave host ip and guest ip blank but that doesn't even open a listening port. If I assign a fixed IP to the head node and use that as the guest ip and 127.0.0.1 as the host IP it works fine. Am I missing something in the documentation or looking in the wrong place, perhaps at an older version?
I think I have it working, but too much black magic and not enough understanding why I had to do what I had to do. Any discussion or insight would be greatly appreciated.
Thanks,
Joe