i don't know if it is specifically "fail2ban", however the firmware does have a "maximum remote login attempts" setting with time intervals.
you would have to make a firewall rule to disable local SSH. I am not sure why you would? What if it goes wrong and you need to fix it?
i don't have an answer regarding rpcbind.
however as with most things, if you try hard enough you can enable/disable anything/everything.
https://lantisproject.com/downloads/gargoylebuilds for the latest releases
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