Show all DHCP addresses on main router

Installing and Using OpenWrt Network and Wireless Configuration
1

I am no expert so please excuse me that I need to stress that topic again. I see lot's of similar questions but all not about that in my eyes simple thing.

The main router doesn´t display all DHCP and IP addresses in my network.
I don't need that information on the APs just would like to have it on the main router. Can I improve that? How do you manage your IPs?
All are OWRT devices on 24.10.1, one main router serving DHCP and 3 DumbAP configured routers.

Questions

  1. Devices maintained with a static IP, not in the DHCP range, and connected to a DumbAP are not displayed on the main router
  2. Lot's of devices don´t show their host names, can I improve that?
  3. I set DHCP allocate sequentially but there is one big gap in the leased DHCP addresses. Why is that and can I correct that? Some but not all are devices connected to the APs - is there a kind of range reservation for APs?
2

if static IP is set on the client, not in openwrt's DHCP, the router stats page won't "see" it.

not all devices will share a host name with the DHCP, you can see this if you sniff the DHCP traffic using tcpdump.

3

But I think some of these devices are visible even when static IP is set on the device, but all of them are connected to a AP not to the main router, it seems they do not talk to each other

And when it is possible to tcpdump that, can it not be added to the list view in O-Wrt?
How to use this tcpdump command?

4

tcpdump -i any -p port 67 or port 68

The -i any -p means listen on any interface (and disable promiscuous mode, required for any), you'll also get WAN/upstream DHCP in this. You can focus on a single interface/device instead (use names from ifconfig -a). You can drop the -poption in that case.

If devices offer hostnames they will be used in this output, the -n option can be used to enforce numerical addresses only.

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5

I will definitely try that.
Maybe one thing, the list output does it get stored somewhere, or is it just online readable?

6

the tcpdump output is for the traffic passing the interface(s) there and now, but you can save the output, if you'd like.

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