3120 adds en2 and en3 networking configurations

Does anyone know what these do? I only run wirelessly and disabling these seems to make no difference.

 

en2 is for the Host-Only Networking option.
en3 is for Shared Networking.

 

Could you explain what this means?

 

Host-Only Networking allows the VM to open network connections to the Host OS (and vice versa).
Shared Networking also allows the VM to open network connections to the Host OS but it also establishes a NAT with your external networking interface on the Host. This allows your guest to access anything upstream of your host (like the internet) without needing another external IP address or needing to deal with broken bridging on wireless interfaces.

Hope this helps.

Ryan

 

So I should keep both of these enabled in network preferences?

 

yes. unless you have a dire need not to. If you decide to switch networking modes between Shared, Bridged and Host-Only, you will have difficulty if they are disabled.