@Solla-topee 

Thank you for your quick rely!

Regarding " you could unplug powerline unit and see if Modem could work stable ":
This is quite difficult, because the DSL loses sync very irregularly, therefore I would probably have to wait a day or two to monitor the effect. However, I need the powerline to have at least some internet in my home office room.

I simulated a DSL sync loss by unplugging the DSL cable. The PLC did not start a DHCP server. Consequently, it did not stop one when the DSL sync was back.

However, at least in my setup a loss of the DSL sync does not mean that my Router (which includes the DSL modem) turns off its DHCP server. So the PLC will all the time see a DHCP running, even if the Router loses DSL sync for a long time.

In addition, I several times encountered the situation that I had no internet connection via PLC but when I directly connected to the LAN or WiFi of my Router the internet connection was fine. In these cases PLC did start a DHCP server without any DSL sync loss correlated to that.

@TP-Link Absolutely increduluous to learn there could be a hidden DHCP server in a network device. I think most system admins would be shocked at discovering a rogue DHCP server on their network. I've spent countless hours diagnosing a Teltonika RUT950 router on which I have spent much money too. I've factory reset it and rebuilt it at least 5 times. It came crashing down again yesterday. I was on the verge of throwing it out. Today I discovered the problem was with a WPA4220 I'd bought some months ago. I'm horrified. I have great regard for TP Link and I have recommend the companies products widely, but on this occassion the company has performed poorly. Clearly this problem was known about for a long time, yet the response has been poor.

I'm experiencing the same issue as many others on this thread using a WPA4220 v5. I'm answering the questions previous posters have been asked below:

1. How did you find out powerline device's DHCP server does not work properly? Did you often reboot main router or is there often power outage in your house?

This issue occurs randomly, the main router does not need to experience any issues for the "smart DHCP" to start up. After reviewing other posts and spending many hours on this I've reviewed the system logs of the powerline adapter which show the DHCP server is starting up, assigning 4 IP addresses, and then disconnecting a few minutes or seconds later. I'm using the Static IP option so there should be no DHCP server enabled at all.

2. Does router’s internet work fine at that moment?

The internet works fine for devices connected directly to the router but not to the powerline adapter.

3. LED status on both powerline units.

Power, powerline and wireless lights are all on.

4. Brand and Model of router:

Virgin Media Superhub 3.0

Your network topology, for example:

ISP modem --- Router Archer C7 --- PA8010 .... <powerline> ...WPA8630P --- Asus laptop model XX.

Virgin SuperHub 3.0 router --- TL-PA4010 wired powerline --- TL-WPA4220 wireless powerline --- multiple devices e.g. phones, laptops, etc.

5. Model & OS of devices that connected to wireless powerline unit.

Android 9 Xiaomi Redmii Note 8 Pro

Android 11 Google Pixel 4XL

Windows 10 laptop

Google Nest Mini

6. Model number & firmware and hardware version of your powerline KIT, update the firmware if it is not the latest version:

V5. Firmware version: 1.0.1 Build 200811 Rel.68784n (6985/8575)

Powerline connections may not be as reliable as ethernet. Since the WPA devices are more than likely to have a powerline segment between them and the router, any disruption to the powerline link, perhaps even momentary, might result in the WPA losing connectivity to the DHCP on the router and enabling its own DHCP server. I suspect this is the cause in many cases.

(I don't think anyone is connecting the WPA to the router by ethernet - if that was the plan we wouldn't buy a powerline product in the first place.)

And how much unnecessary broadcast traffic is the WPA generating to detect if a DHCP server is running somewhere on the network?

Enable disabling Smart DHCP already!

Same problem, deploying 4x TL-WPA4220 V5 at somebodies place...

At first I configured them to use DHCP client, this was totally unstable as they requested an IP every 30 seconds!

Now I have configured fixed address, and even after rebooting they are STILL requesting an IP address from DHCP.

Totally broken FW if you ask me.

System log of a unit:

1 INFO 0days, 00:00:00, LAN:Attach mirror0 to stack.

2 ERROR 0days, 00:00:00, SNTPC: select sntpc local port 29835..

3 INFO 0days, 00:00:00, LAN:Set interface mirror0 ip=192.168.89.11 netmask 255.255.255.0.

4 INFO 0days, 00:00:00, DHCPS: Dhcps start

5 INFO 0days, 00:00:00, HTTPD: Http server start!

6 INFO 0days, 00:00:07, DHCPC: Start DHCPC

7 INFO 0days, 00:00:13, DHCPS: Recv DISCOVER from 00:31:92:5D:6B:9A.

8 INFO 0days, 00:00:14, DHCPS: Send OFFER with ip 192.168.89.102.

9 INFO 0days, 00:00:14, DHCPS: Recv DISCOVER from 00:31:92:5D:6B:9A.

10 INFO 0days, 00:00:14, DHCPS: Send OFFER with ip 192.168.89.102.

11 INFO 0days, 00:00:14, DHCPC: Recv OFFER from server 192.168.89.1 with ip 192.168.89.39

12 INFO 0days, 00:00:14, DHCPS: Dhcps stop

Router is a Mikrotik (RouterOS)

Really need a fix that disables DHCP server and client (when static Ip is set) !!!

@Solla-topee 

If it's the same beta that installed a few months ago, then it doesn't fix the problem - it still starts the DHCP server on powerup for approx 12 seconds. 

I'm still waiting for TP-link to sort out what should be a trivial issue to fix. Meanwhile my WPA device is gathering dust on the shelf. Total waste of money. 

Come on tp-link you can do better than this - this is a complete shambles.

@TP-Link  I called to your support line and I got information that you will NOT prepare new firmware for this model (WPA-7517) because is not longer in sale. Is it true?