Thank you for contacting Lennar Home Community.
Hope you are doing well!!!
As per the case description, I could understand that your RUCKUS setup is not working after replacing a modem.
As you mentioned that your modem is directly connected to the ICX-7150-C12P Switch, it doesn’t work only with Modem. The connection must be from a Router or Modem-Router combo device. Could you please confirm this once?
Please refer to the short guide link below about how to connect the devices as a reference:
Most common Setups for Lennar homes users:
Please let me know if you have any queries in this regard.
Thank you again.
Lennar Home Community.