Router ↔ firewall link
- Input
- 10.0.0.1/30
- Expected output
- Rede 10.0.0.0, hosts .1 e .2, broadcast .3
Classic short-link case.
cidr 30
CIDR /30 explained
A dedicated /30 landing makes sense because this mask shows up frequently in point-to-point links and network troubleshooting.
Why /30 is special
- With /30, only 2 host bits remain, resulting in 4 total addresses.
- In traditional IPv4, that leaves exactly 2 usable hosts — a classic link between two devices.
/30 examples
Mask
- Input
- /30
- Expected output
- 255.255.255.252
A good mask for studying older links.
Full tool FAQ
Yes. It helps visualize the main subnetting outputs for both IPv4 and IPv6, including split scenarios and more detailed planning workflows.
Frequently asked questions
How many hosts does /30 have?
In common IPv4, 2 usable hosts.
Is /30 still used?
Yes, although /31 also appears in some modern scenarios.