The remaining 1 retained it's main network IP but updated after about 5-10 min to the correct subnet IP.
That’s odd behaviour but I have seen instances where the network map reports it having joined one subnet but is actually configured to only ever join another.
Just mulling it over, it’s either, as stated above:
(a) a network map anomaly in the notoriously unreliable** Asus Network Map screen, for which you really don’t need to worry or
(b) you’ve duplicated SSIDs (Main/IoT) and as such inadvertently configured the device to be able to join the main subnet OR the IoT one and it eventually migrates to the IoT one. This is highly unlikely. Or
(c) The device can save multiple SSIDs on either channel and if it can’t join one will cycle to a previously saved one. IIRC my Alexa Echo Dots have this capability and it wasn’t until I deleted an old 5Ghz profile on main did they migrate to my preferred 2.4Ghz one on the IoT network. Unlikely though as once latched on to a network they don’t tend to move.
** For (a) you may want to look at the System Log, DHCP leases menu instead, but it has a glaring drawback, it remembers the lease data for as long as the lease is set, so even if a device detaches, it shows the cached lease information which can be hours old. You could try to issue
service restart_dnsmasq but I’m not sure that will force it to show the most up to date information. The RHS column does nicely list which VLAN the devices are latched on to though.
Separately, the System Log, wireless log menu is a nice tabular layout and would be ideal… if it weren’t for the fact it only lists devices connected to main.. sigh.
Another option would be be, via a Cmd Line if you’re comfortable with SSHing to your main router, is simply issue this at the prompt: ugly but ok for troubleshooting. It does depend on how often the ARP cache is flushed though, although I think this is very much more frequent than DHCP leases (60s to minutes) IIRC. You’ll probably be able to see when a device connects to what node on what VLAN sooner too. It might be that it has actually connected correctly right away, just the ASUS network map needs to scratch its head and cogitate like some contented ruminant.
A third option, but by no means the last is
RTRMON by the incomparable
@Viktor Jaep. It’s an all singing all dancing script you run from amtm (as you don’t have a sig yet, and posted just 3 messages, I can’t see if you have installed any scripts before, so if your eyes glazed over right now don’t worry, you’re not the first). RTRMON has sufficient screens (see screen 7) to give the average person the mother of all headaches, but is very useful all the same. Good for troubleshooting.
... a router reboot should renew the leases so hopefully that will fix it. Easy enough to do (as long as the family are not online ... otherwise go sit in the naughty chair...)
