Nmap tracker - 5GHz woes

I’ve just realised why nmap has gone from being my most reliable tracker to my least reliable - it does not register the phone as being on the network if it is connected via 5GHz wifi rather than 2.4Ghz wifi.

The phone has the same mac and IP regardless of connection method.

Not sure if this a phone, router or HA component problem or if there is any way to tell.

which component are you using?

Not likely to be phone.
maybe it is switching between 2.5 and 5. When change to 5 it may just delay long period before show again.
you can try disable 2.5 and see if device show when on 5

It’s in the title and first sentence of the post.

If I delete the 2.4GHz connection from the phone and stay connected to the 5GHz wifi all day, nmap does not register the phone as being at Home.

As soon as I disconnect from 5GHz and connect to 2.4GHz wifi the nmap tracker is set as “Home”.

I have checked the mac address (arp) and IP address (ping) and confirmed they are the same for both frequency bands.

2.5 and 5 use same ssid?
are 2.5 and 5 same IP space?

No. One is [SSDI], the other is [SSID]_5G.


I used nmap with my network until very recently. I had separate 2.4 GHz and 5 GHz SSIDs. NMAP didn’t care which SSID a device was connected to, because it’s not aware.

If there’s a problem, then it’s with the configuration of your WiFi router/access point. Check that there’s no differences in, say, client separation settings etc.

Yeah that’s what I would have expected. It’s not what I’m seeing though. The only client separation rule is for the guest wifi network which is disabled.

Using Zenmap I see no difference between scanning the phone’s IP on 5GHz or 2.4GHz.

Very strange as NMAP just scans the network, so if your on the network, job done.

U’ve not got any setting like WLAN isolation set (tho u say zenmap shows no diffrence)

To test i would do the following from the machine running HASS, connect to 2.4Ghz, use NMAP to scan the network. Note it all down.
Connect to 5Ghz, use NMAP to scan the network again.

Also might be worth doing a traceroute to your phones IP and hoping between 2.4 and 5 to see if the access point is not releasing the MAC address (if separate APs for 2.5 and 5)


on linux is quite good for digging into trace routes.

Since running the zenmap tests I’ve left the phone on the 5GHz network and for now it is staying registered as “Home”.

I’m beginning to suspect the phone. Not long ago I had troubles with connecting to the HA Aircast addon until I cycled the phone’s wifi.

A search reveals a lot of wif problems with the recent ios 11.4.1 update.

Just tried an over the air sync with iTunes. 5GHz kept dropping out. 2.4GHz was rock solid. The phone is 2m from the access point. It’s either interference or a problem with ios 11.4.1.

Do u have any other 5Ghz devices (non apple) at you can compare with ?

I have a Surface Pro 4. I just ran inSSIDer to see if there were any interfering channels. There weren’t. I’m now doing a large copy across the 5GHz network to the SP4 to see how that goes.

It’s definitely the phone. Copied 100s of GB from and to the SP4 using the 5GHz wifi without issue. Also the phone is now dropping off the 2.4GHz network as well. Have stopped using nmap. Owntracks is still reliable(ish). Tracking was better with both trackers combined but until an ios update is released I’ll just turn off my location based automations.