The Smell of Molten Projects in the Morning

Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.

The New Hotness

  • Raspberry Pi vs. Avahi

    It turns out that the various Avahi daemons performing the magick between whatever.local names and dotted-quad 192.168.1.101 addresses for Raspberry Pi descend into gibbering madness when confronted with:

    • One name corresponding to multiple IP addresses
    • One IP address used for multiple MAC addresses
    • Multiple names for one IP address
    • Multiple names for one MAC address
    • Multiple IP addresses for one MAC address
    • Multiple MAC addresses for one IP address
    • Any and all combinations of the above at various times

    The least of the confusion involved an incorrect IP address linked to a familiar name pulled from deep history by a baffled daemon doing the best it can with what it thinks it knows. Despite what I concluded, rather early in the process, there’s no real error, other than my performing what amounted to a self-inflicted fast-flux nameserver attack.

    Anyhow, I devoted the better part of an afternoon to sorting out the mess, which involved labeling all the streaming radio players with their MAC addresses and rebooting them one-by-one to allow all the daemons time to recognize the current situation:

    Raspberry Pi 3 - WiFi MAC address
    Raspberry Pi 3 – WiFi MAC address

    That label corresponds to the Pi 3’s on-board WiFi adapter.

    For Pi 2 boxen, the MAC address travels with the WiFi adapter jammed into a USB port:

    SunFounder WiFi Adapter - MAC address
    SunFounder WiFi Adapter – MAC address

    I didn’t label the (unused) Ethernet jacks, figuring I’d solve that problem after it trips me up.