A node is a daemon running on a machine. You can install the daemon on multiple machines, and manage them from the server (i.e.:GUI). The GUI or TUI acts as the server.

ℹ️ Note: if you want to install only the daemon from the Debian repositories, you'll have to execute this command:

$ sudo apt install --no-install-recommends opensnitch (otherwise it'll install both, the daemon and the GUI)

You can view the list of connected nodes from the Nodes tab:

And by double clicking on a node, you can see the network activity of that node.

By default, the GUI (server) and the nodes listen on a unix socket. If you want to manage multiple nodes, you have to change the GUI (server) address from the Preferences -> UI tab.

First change the (server) address of the node from the Preferences dialog, Nodes tab:

The node will disconnect and try to reconnect to the new address.

Then change the address of the GUI (server):

⚠️ Important: Before changing the GUI (server) address, always change the node address. Otherwise you'll have to edit the daemon configuration manually.

You can also launch the GUI from the terminal like this:

$ /usr/local/bin/opensnitch-ui --socket "[::]:50051"

It'll make the GUI listen on port 50051, any IP. You can also use an IP: `$ /usr/local/bin/opensnitch-ui --socket "127.0.0.1:50051"`

ℹ️ Max server workers:

This option affects to how many nodes the GUI can handle. Each node consumes about 2 workers, so the default configuration of 20 workers allows to handle 10-15 nodes. If there're more nodes than workers, the GUI will run out of resources, and won't allow new messages or events from any node.

ℹ️ Max server clients:

Use this option to limit how many nodes can connect to the GUI (server). The default value of 0 allows unlimited number of incoming connections (nodes).

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The GUI also allows to configure nodes' rules, both application and system firewall rules.

When there's more than one node connected to the GUI, every dialog of the GUI will display the list of nodes:

Rule

System firewall rule

Use the Rules tab to view and monitor the rules of all nodes:

and apply actions in batch (delete, apply, .. rules)