Hi Albert,   Viya 4 primarily uses only port 443 (for https) for external communication. If you want to use binary connections to CAS, for instance from SAS 9.4 or Viya 3.5, you need to configure external access to CAS which defaults to port 5570. More information about that can be found here: https://go.documentation.sas.com/doc/en/itopscdc/v_034/dplyml0phy0dkr/n08u2yg8tdkb4jn18u8zsi6yfv3d.htm#n0exq3y1b5gs73n18vi9o78y2dg3   To enable SAS/CONNECT from SAS 9.4M6 or earlier you also need to open a specific, but customizable, port. More information here: https://go.documentation.sas.com/doc/en/itopscdc/v_034/dplyml0phy0dkr/n08u2yg8tdkb4jn18u8zsi6yfv3d.htm#n15zzkfyoys8iyn1e8izqi7rhnan   In addition to this, you might have to open ports for your database connections, network shared disks, email server and similar services, but I expect your IT organization can help you identify those ports.   If you are thinking about ports internal to the kubernetes namespace where Viya lives, there's usually no firewall between nodes/pods/containers.    Regards, Olof Smith, technical architect @ SAS My views and advices here are solely my own and cannot be considered as any official statement from SAS.  ... View more