SNAT: No aliases found

NethServer 7.7.1908

i try to create a SNAT and it says

No aliases found

It seems that you have not configured any aliases. Go to the Network page to configure some.
but i ve created aliases

Alias on a RED interface?

I see…I had no red interfaces…that s why…so why snat is only available on red interfaces?

Where are you willing to use SNAT? Which interfaces are involved?
Consider than a RED interface is by nethserver perspective (interface for connect to internet)