DHCP request without answer

[Ruzsinszky Attila]

Hi,

I don't know what is the problem.

There is a TP Link TL-WR2543 router with OpenWRT sw. It is the DHCP server.
There is a TP Link TL-WA750 WiFi extender as a WiFi/Ethernet bridge. (DHCP
server disabled)
There is an OpenSpinkler (OS) small IP box. It is the DHCP client.

I'm not able to reach the OpenSpinkler. In some days (2 or 3) the OS forget
its IP and not able to get the new one.

Interesting things:
- the lease time is 6 hours (<-> 2 or 3 days disappearing from the LAN!)
- the MAC and IP associated (fix association) MAC -> IP
- if I reboot the extender ASAP the reboot process was finished the OS gets
its IP.

Here is the tcpdump from the router (DHCP server):

(in every 10th secs)
16:18:30.640826 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto UDP
(17), length 293)
    0.0.0.0.bootpc > 255.255.255.255.bootps: [no cksum] BOOTP/DHCP, Request
from 00:69:69:2d:31:00 (oui Unknown), length 265, xid 0x7654fc38, Flags
[Broadcast] (0x8000)
      Client-Ethernet-Address 00:69:69:2d:31:00 (oui Unknown)
      Vendor-rfc1048 Extensions
        Magic Cookie 0x63825363
        DHCP-Message Option 53, length 1: Discover
        Client-ID Option 61, length 7: ether 00:69:69:2d:31:00
        Hostname Option 12, length 5: "OS-00"
        Parameter-Request Option 55, length 3:
          Subnet-Mask, Default-Gateway, Domain-Name-Server

I don't know what is the problem with this request packet!

I connected to the extender a very simple 11Mbps WiFi router and I use it
as an other DHCP client.
It is working!!! I don't understand. (difference between OS and this
router: no MAC->IP assoc.)

TIA,
Ruzsi
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