Building the ACM Cluster, Part 9: Setting up masquerade with iptables
Published on in ACM, ACM Cluster
Alright! Lets get this started again. There is one last thing we need to do in order to have networking on the cluster functional. Right now, the nodes inside the cluster can’t speak to the outside world. While we set up the head node to be able to speak to things on every interface, we haven’t yet told it how to move traffic from one interface to another.
Making the Gateway
In normal clusters, there are three types of notes - workers, gateways and head nodes. Workers do whatever task the cluster is intended for. Head noes manage the workers. And finally, gateways, which allow the worker nodes to communicate with things outside the cluster.
Gateways are needed because clusters often use IP addresses which are not publicly routeable. The gateway allows the entire cluster to sit behind one IP address and is in charge of routing traffic properly. This process is called Network Address Translation. In many ways, this makes the gateway like your home router.
Anyway, …