iptables

root@jam:~# iptables -L -n --line-numbers 
Chain INPUT (policy ACCEPT)
num  target     prot opt source               destination         
1    DROP       1    --  0.0.0.0/0            0.0.0.0/0           
2    ACCEPT     6    --  150.89.233.33        0.0.0.0/0            tcp dpt:1807
3    DROP       6    --  0.0.0.0/0            0.0.0.0/0            tcp dpt:1807

Chain FORWARD (policy ACCEPT)
num  target     prot opt source               destination         

Chain OUTPUT (policy ACCEPT)
num  target     prot opt source               destination         
root@jam:~# 
root@jam:~# iptables -A INPUT -s 150.89.233.33 -p tcp --dport 1807 -j ACCEPT
root@jam:~# iptables -A INPUT -p tcp --dport 1807 -j DROP
root@jam:~# iptables -L -n --line-numbers 
Chain INPUT (policy ACCEPT)
num  target     prot opt source               destination         
1    ACCEPT     6    --  150.89.233.33        0.0.0.0/0            tcp dpt:1807
2    DROP       6    --  0.0.0.0/0            0.0.0.0/0            tcp dpt:1807
root@jam:~# iptables -I INPUT 1 -p icmp -j DROP
root@jam:~# iptables -L -n --line-numbers 
Chain INPUT (policy ACCEPT)
num  target     prot opt source               destination         
1    DROP       1    --  0.0.0.0/0            0.0.0.0/0           
2    ACCEPT     6    --  150.89.233.33        0.0.0.0/0            tcp dpt:1807
3    DROP       6    --  0.0.0.0/0            0.0.0.0/0            tcp dpt:1807

Chain FORWARD (policy ACCEPT)
num  target     prot opt source               destination         

Chain OUTPUT (policy ACCEPT)
num  target     prot opt source               destination         
root@jam:~# 
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