I'm currently deploying on Rackspace Cloud Servers with Debian installs.
I have an application that uses a remote coordinator which communicates with all of my servers in order to start various services and just to generally keep track of the servers.
I need to secure my production environment and I'm using certain services (Couchbase/Membase and ElasticSearch) that don't have built in security so I need to implement a firewall on all of my servers. The coordinator can be modified to provide firewall rules for the servers to implement, but I don't know how to modify firewall settings in Debian programmatically. I would like to be able to specify ports just to lock it down a bit tighter.
If anyone has any advice on how to achieve this or can see that I'm doing something wrong then please let me know.