Hi Ajohnson,
If replacing irb with ge-0/0/0 works fine, I suspect that the switching mode might not have kicked in.
Please run the following command and look for switching mode. It should be set to "Switching" .
> show ethernet-switching global-information
Global Configuration:
MAC aging interval : 300
MAC learning : Enabled
MAC statistics : Disabled
MAC limit Count : 16383
MAC limit hit : Disabled
MAC packet action drop : Disabled
LE aging time : 1200
LE VLAN aging time : 1200
Global Mode : Switching
If this setting looks correct, please reboot the device once.
If this setting does not look correct , set it manually and then reboot it.
set protocols l2-learning global-mode switching
Thanks!