BIG-IP LTM Dynamic ARP Table Visibility

The ARP protocol is used to resolve layer-3 addresses to layer-2 addresses. Since the LTM never needs to ask this question for directly connected interfaces, those will not be present in the table.

You could try pinging the broadcast address (make sure you use -b), or the multicast 'all hosts' address (224.0.0.1) to elicit traffic from other devices.

Alternatively, use a linux device connected to the same subnet and run nmap 10.0.0.1-255 (adjust for whatever your subnet is)

And if you can't do that, script it:

for i in {1..254} ; do ping -W1 -c1 10.0.0.$i ; done ; arp -na

With a 1-second timeout (-W1), that will take a little over 4 minutes.