Mikrotik gate setup (example)

setup
a
ether2
10.80.140.1/24
a
ether1
10.80.1.140/16
g
10.80.1.1
ip dns edit servers
10.80.1.1
8.8.8.8
CTRL+O
ip firewall nat add chain=srcnat action=masquerade out-interface=!ether2
ip firewall filter add chain=forward dst-address=10.80.140.5/24 action=accept
ip firewall filter add chain=forward src-address=10.80.140.5/24 action=accept