Some questions about static IP address

How do you configure a static IP for the start9 server?
Can this be done AFTER installing knots?
Is there a recommended DNS server(s) to use when configuring IP?
Thanks.

This would be done from your DHCP server, likely built into your router. This is what distributes IP addresses to devices that join your network. Most people reserve the first 10 or so using the router software, then assign one permanently to a specific device… in this case your server.