iptables allow port 22 example
Of course change --dport and -s to suit your needs
#allow certain IP to access port 22
iptables -A INPUT -p tcp -m tcp --dport 22 -s 192.168.1.0/24 -j ACCEPT
# block others
iptables -A INPUT -p tcp --dport 22 -j DROP........
I bricked one of my cards by following a guide from UNRAID.
Step #1 from them wipes out the BIOS, but guess what? The step where you restore the BIOS should have been done first, which is sas2flash but no version supports or is able to find my Perc 6/i. So now I'm a bit stuck.
I tried using megarec but it's funny that it can wipe the BIOS but can't forcefully reload it:
megarec -writesbr 0 mpt2sas.rom
Supports 1078 control........