Intrusion Detection - whitelist network?

I’m using the intrustion detection in FreePBX - Admin - System Admin - Intrusion Detection and put in 192.168.1.0 for a network address in the whitelist but PC 192.168.1.11 got banned. Do we have to put in 192.168.1.0/24 to indicate the network mask? Will it accept networks? When manually configuring Fail2ban, you could indicate network addresses to whitelist.

Yes, it needs the netmask so in your case (assuming a Class-C Network) it would be 192.168.1.0/24.