NETWORKING • PRACTICAL UTILITIES
Network Tools
Quick, browser-based helpers for everyday networking work and CCNA practice. Calculations run locally in your browser; no input is sent to a server.
01 / ADDRESSING
IPv4 subnet calculator
Enter an IPv4 address and prefix length to calculate the subnet details.
Note: /31 is commonly used for point-to-point links (both addresses usable); /32 represents a single host route. This calculator shows the conventional network/broadcast model for the range, with those special cases reflected in host counts.
02 / SWITCHING
Cisco VLAN config builder
Generate a basic access-port or trunk configuration. Review the interface and VLAN IDs before pasting into a device.
Generated Cisco IOS configuration
configure terminal
vlan 20
name VLAN20
exit
interface GigabitEthernet1/0/10
description Configured-by-Network-Tools
switchport mode access
switchport access vlan 20
no shutdown
end
This is a starting template, not a substitute for your organization's standards. Trunk syntax and supported features can vary by platform and IOS version.
03 / QUICK REFERENCE
Common Cisco IOS checks
Copy commands for routine verification. Confirm command availability on your device and follow change-control procedures.
show ip interface briefQuick view of Layer 3 interface addresses and status.
show interfaces statusPort status, VLAN, duplex, speed, and media summary on supported switches.
show vlan briefList VLANs and access ports assigned to each VLAN.
show interfaces trunkCheck trunking state and allowed/active VLANs.
show mac address-table dynamicInspect dynamically learned Layer 2 MAC addresses.
show ip routeReview the IPv4 routing table and route sources.
show loggingReview recent system messages and troubleshooting clues.