I'm trying to use the solution https://notenoughtech.com/home-automation/nodered-home-automation/nodered-whos-home/ to know who is at home but it does not work. When I put a MAC address in the node, there is no filtering on output.
The device could be connected or not connected to the network, I have in both case a big array with all IP adresses in the output. Have you ever had this problem?
I just used to run arp scan in an exec node with a custom config file. It returns everything it knows about or can see.
I stopped using that for presence detection though as it doesn't work reliably at all. Presence in the arp table does not imply that the device is actually present in reality, nor does absence in the table necessarily mean that the device isn't in the building.
@TotallyInformation Jullian, what are you using in place of arp?
Nothing, I've not found anything reliable enough to bother with.
Bluetooth tags or even NFC tags would do it if you have limited entrances/exits. Or, if the family are willing, you could set up geofences on their phones (realistically only accurate to a 100m+ or up to 1/2mi in some cases) and of no help if someone forgets their phone or it runs out of power. But honestly, it is all too much faff.
What I do intend is to create an arming script for when we are all out. Someone can simply flip a switch to arm and again to disarm. Possibly with a small bleeper on an ESP device near the front door.
Monitor is very reliable in most instances. I say 'most' because it picks up 3 of the 4 phones I want to monitor very well. It doesn't seem to like my eldest daughter's phone though. I have it running on 3 Pi's (one 3B+, 2 zeroes) around the house and none of them reliably find her phone. I haven't really investigated why.
It looks like it interferes with the 2.4GHz wifi too, so I only scan every 15 minutes (plus on motion), whereas normally I think it's every 15 seconds.
Which kind of sums up some of my issues with BT.
Firstly, you need devices to cover the whole building - a challenge in a big old Victorian house like mine with stone walls and original plaster & lath internal walls.
Then there are the oddities of BT which are legion. In previous attempts to play with beacons for example, I could pick up people walking past in the street (from 3-floors up in the loft) but I could not pick up my own phone no matter what!
Still, a useful link thanks. I've added it to my list of "things to look at later".
you are right, arp is not a good solution: devices are not always in the table. I though that the solution would be simple but it is not. As @TotallyInformation said I add the task in my TO DO LIST for later.