Thanks for the reply. I had looked at that guide but I don't see where it says specifically that you must set arp-inspection on at the same time with ip-source-guard.
I see where you said " On the EX4300 when you enable any Security feature, like IP-Source Guard, the switch automatically enabled Dynamic Arp Inspection (DAI), which is a requirment for IP-SG to work." Did you mean it automatically enabled dhcp-snooping or DAI? The doc you posted says "
- If your switch uses Junos OS for EX Series with support for the Enhanced Layer 2 Software (ELS) configuration style, DHCP snooping is enabled automatically when you enable IP source guard on a VLAN. See Configuring IP Source Guard (CLI Procedure)."
It just never occured that both had to be on because coming from the Cisco world they work independantly of each other.
Sorry for the newbie Questions.