WZR-1750DHP: getting new WAN address for no reason

[efan]

Hi All

I've searched the forums for a bit but couldn't find anything.

My air station is connected via cable to my router from my ISP (bridged mode) and receives it's WAN address via DHCP. My ISP has no time limit on IP leases so I've been using the same IP for about 5 years now with homemade firewall server directly connected to the router. Yesterday I switched to the airstation and I noticed it was getting a new ip address every reboot. I tried using my old MAC address for the DHCP request which resulted in getting my old IP back - until the next restart. since then every time the station reboots (or I have to reboot it because it becomes inaccessible) it's getting a new ip address.

this is especially vexing since I'm using services which are IP based and require me to login again and again due to the constant changes.

I further noticed the station is losing it's date and time every reboot (and NTP times out for no reason, despite the station being able to ping the NTP server). is this normal behaviour or is something wrong with the hardware?

and if something in my setup might be the cause of these problems, here a few more details:
- one WZR-1750DHP (base) is connected to the ISP's router, and it has the DHCP server for clients enabled
- another WZR-1750DHP (bridge) is in another room acting as a bridge (with the switch at the back toggled) to the wifi base station and connected to a switch
- on my switch all my other hardware is located, server, clients and so on
- there's another (authorative) DHCP server in my network for internal IPs and so far it has worked in overriding the base stations DHCP (I still leave it active for easier connection when debugging with a cable or something)
- both stations use the 2.29 firmware (I tried ddwrt before but in speedtests it was only getting about 20mbit of my 250mbit downstream so I went back to the official firmware which can transmit the full 250mbit and maybe more, should my ISP upgrade again)

any help in solving this problem is appreciated.