Similar as on FreeBSD and Linux, you can add/remove static network routes through the command line with the route command. The syntax somewhat differs from Linux, though.
To add a route (e.g. subnet 192.168.3.0/24 to gateway 192.168.1.254):
sudo route -n add -net 192.168.3.0/24 192.168.1.254
To remove a route:
sudo route -n delete -net 192.168.3.0/24
To show the current route table, you can use netstat:
Cisco's SF/SG 300/500 series managed switches have CLI access via Telnet and SSH but this is turned off by default, leaving only the web interface to manage the switch. You can enable Telnet and/or SSH via the web interface, enabling management via CLI.