Title: Check Open Ports
Description: Check a device you own or are authorized to test for responding network ports
URL: /latest/wifi/port-scanning/
Version: latest
Section: Wi-Fi
Search index: /search-index.json

# Check Open Ports

> Check a device you own or are authorized to test for responding network ports

## On this page

- [Scanning ports](#scanning-ports)
- [Troubleshooting](#troubleshooting)

---

Port scanning checks which network ports on an authorized device respond to connection attempts, so you can inventory services on your own network. [Connect GhostESP](/latest/wifi/connect/) to the same network and identify the device with [LAN discovery](/latest/wifi/lan-discovery/). Only scan devices you own or have permission to test; see [Legal and ethical rules](/latest/wifi/basics/#legal-and-ethical-rules).
## Scanning ports
- Open Menu → Wi-Fi → Network while GhostESP is connected and choose Scan Open Ports, then review the responding ports.
From the CLI, run scanports <ip> to check a specific device’s TCP and common UDP ports. Add all to check all ports, or a range such as 20-1024 to limit the scan. Run scanports local to scan every host on the local subnet (takes no arguments; uses the async sweep). Run scanssh <ip> to check whether SSH responds on a device, or scanssh with no argument to scan the local subnet. Run scanarp monitor [seconds] to watch the network for new hosts while you scan.
What a port scan does
1
Resolve the target, or reuse a prior scan`scanports <ip>`, `local` for the subnet, or an ARP sweep first
2
Send TCP connection attemptsCommon ports by default, `all`, or a `start-end` range
3
Send UDP probes to common services`scanports <ip>` also checks common UDP ports
4
List the ports that respond`scanssh <ip>` checks SSH specifically
A missing result does not prove a service is absent; firewalls and network policy can block scans.
GhostESP lists the ports that respond. A missing result does not prove that a service is absent; firewalls and network policy can block scans.
## Troubleshooting
- No ports respond: Confirm the IP address, network connection, and whether the device has a firewall.
- The wrong device is scanned: Run LAN discovery again and verify the IP address before retrying.
- The scan is slow: Limit the port range to the services you need to inspect.