Re:Show HN: Whosthere: A LAN discovery tool with a modern TU...
by 84634E1A607A on Friday January 23, 2026 @09:15AM
(#46732737)
Overall good work. I'd request an `-i` command-line parameter to specify the interface to scan (and I'd prefer ALL params being able to be read from command line params). I think it just performs a full scan initially on my laptop, following scans either didn't success or didn't involve TCP connect scan (I don't see ARP requests after the initial scan).
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Re:Show HN: Whosthere: A LAN discovery tool with a modern TU...
by rvermeulen98 on Friday January 23, 2026 @09:36AM
(#46732986)
That's correct. To avoid overloading the local network, the initial scan has a built-in safeguard:
1. It only scans the subnet of the configured network interface.
2. The scan is limited to a maximum size of a /16 subnet.
3. It runs just once every 5 minutes (this interval should be made configurable, currently still hardcoded).
If a subnet larger than /16 is configured, whosthere will log a warning and only scan the first /16 portion of that subnet. As of now the network interface itself is configured via the YAML file. I agree it would be a good idea to add command-line flags for more of these settings to make them easier to adjust.