3000 tracked connections aren't so much ....
anyway, try only
ubnt@ubnt:~$ configure [edit] ubnt@ubnt# set system conntrack ignore rule 10 destination address 255.255.255.255 ubnt@ubnt# commit [edit] ubnt@ubnt# save Saving configuration to '/config/config.boot'... Done [edit] ubnt@ubnt# exit exit ubnt@ubnt:~$
Cheers,
jonatha