Observium unable to resolve IP's on lan network

[tbrand1968]

Hello, I'm running your docker install of observium, I've left everything default and am trying to add on machine via IP address. However, it's unable to resolve the IP even though it is on the same lan.
I run observium in my work environment and am familiar with how it works setting up SNMP devices, but for the life of me can't get this docker to install a new device.
Any thoughts?
Thanks. Tim