Vyos dhcp server giving same ip address to 2 clients

hello i have noticed since long time now vyos(latest rolling release) dhcp server giving same ip address to my access point (i cant configure static ip on it ) and to some random device in network usually error happens after restart of access point (i restart my vyos & access point every night using a timer )

standard basic setup

vyos@vyos:~$ show dhcp server leases
IP Address    MAC address        State    Lease start          Lease expiration     Remaining    Pool    Hostname             Origin
------------  -----------------  -------  -------------------  -------------------  -----------  ------  -------------------  --------
10.255.10.50 5:0f  active   2024/10/10 06:57:48  2024/10/11 06:57:48  23:39:44     LAN     la-s-s22-ultra  local
10.255.10.51  80:ed  active   2024/10/10 07:02:07  2024/10/11 07:02:07  23:44:03     LAN     himura.              local
10.255.10.52  48b  active   2024/10/10 01:48:23  2024/10/11 01:48:23  18:30:19     LAN     msi.                 local
10.255.10.53  3:27  active   2024/10/10 06:56:36  2024/10/11 06:56:36  23:38:32     LAN     redmi-note-9         local
10.255.10.54  52:cb:04:5f:1b:8f  active   2024/10/10 06:57:24  2024/10/11 06:57:24  23:39:20     LAN     zes                local
10.255.10.55  48:bb  active   2024/10/09 21:57:34  2024/10/10 21:57:34  14:39:30     LAN                          local
10.255.10.56  2e:c0:54  active   2024/10/10 04:37:39  2024/10/11 04:37:39  21:19:35     LAN     viv-s-phone          local
10.255.10.57  be:cf:68  active   2024/10/10 06:57:45  2024/10/11 06:57:45  23:39:41     LAN     viv                  local
10.255.10.58  9c:36:a2  active   2024/10/10 04:38:34  2024/10/11 04:38:34  21:20:30     LAN     redmi-note-9         local
10.255.10.59  d2:1e  active   2024/10/10 07:01:12  2024/10/11 07:01:12  23:43:08     LAN     lgwebostv            local
10.255.10.60  0:af:3d  active   2024/10/10 06:56:23  2024/10/11 06:56:23  23:38:19     LAN                          local
10.255.10.61  76:59:f3:64  active   2024/10/10 06:57:42  2024/10/11 06:57:42  23:39:38     LAN     vv-s-phone          local

In the list you show I can’t see any IP assigned to two devices, what are the device names of the two devices? And how big is the IPv4 DHCP pool?

yes thats what i dont know why this happens ,only way out for me is to use static ip for important devices, ip range is 50- 100 ,very basic setup .
My guess is the chinese router keeps changing its ip after restart like in this case 10.xxx.255.60 was assigned both to the access point and to my shield device which was wrong ,how can a (ap in this case)device bypass vyos dhcp server and take a duplicate ip address.

Can you have a look at the clients DHCP client logs? Would be interesting to see if the clients send out a regular DHCP request and if they really get both the answer from VyOS with the .60 IP.

Could be a bug in the DHCP server (ISC KEA) .

the funny thing is i set static ip for 3 devices like 2 nvidia shield they respond properly as per static table ,but the router even though it has a static ip it doesnt respect it ,but takes a complete new ip address

LAN     10.255.10.0/24  miwifi-ra70     10.255.10.5   9c:xx:xxe:7c:xx:14  N/A     N/A
LAN     10.255.10.0/24  nvidia-Bedroom  10.255.10.3   00:xx:xx:48:af:3d  N/A     N/A
LAN     10.255.10.0/24  nvidia-Hall     10.255.10.2   48:x0:xx:13:xx:bb  N/A     N/A

10.255.10.66  9c:xx:xx:7c:xx:14  active   2024/10/11 04:36:28  2024/10/12 04:36:28  6:19:58      LAN     miwifi-ra70          local

See the same device miwifi-ra70(accesspoint) showing in dhcp in different address,i tried factory resetting it first time it will take the static ip but after restart again goes to some random ip range ,so i wonder how can VYOS not control this device???

Can you have a read through this Dhcp client on LAN gets wrong (non-static) lease thread?

That may be the issue you’re facing.

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