Subnet Calculator
IP & Mask or CIDR:
Linux:
Netfilter Log Format
Netfilter Log Format Issues
Linux Firewalls
What is the difference between REJECT and DENY?
Use IP & CIDR Netmask:
10.0.0.1/22
Or IP & Netmask:
10.0.0.1 255.255.252.0
Or IP & Wildcard Mask:
10.0.0.1 0.0.3.255