Devices lose WiFi connection and then "fail to obtain IP address" when trying to reconnect
I appologize this post is a bit long, but here's the executive summary of the issue I'm having:
My network of 5 Deco units (2 M9 Plus & 3 M5's) keeps dropping devices off the network and those devices try to reconnect but get "Failed to obtain IP Address" errors and never reconnect. The only solution I've found is to completly power down my entire house via the circuit breaker and slowly enable power around the house to reconnect a few devices at a time. Then it's only a matter of days before devices seem to start dropping off again!
Feel free to read all the details below if you're interested or can help! Thanks!
More Detailed Story:
I had 2 Deco M9 Plus units in my house working well for the past year. I have been adding more and more wifi devices over the last year, and now there are typically about 60 devices connected at any time. About half of those connected devices are TP Link Kasa smart switches/plugs. To handle the increased capacity and get better coverage at the extremities of my house, I decided to add a few more Deco units to my setup. About a two months ago, I purchased 3 Deco M5 units and added them to my network.
As I built out the network connecting each new Deco unit or new device, things seem to work just fine. However, in the last few weeks, I now have severe issues with devices getting disconnected and not being able to connect back to the network. The devices all attempt to connect to the network but get “Failed to obtain IP address” errors. For example, at some time between 8am and 10am this morning about 25 of the 60 devices on my network were somehow disconnected and have not been able to reconnect for the last few hours.
There seems to be no pattern or reason as to when or why these devices disconnect (or fail to reconnect). This seems to happen every couple of days now and has probably happened 5-6 times in the last two weeks. And it's a different group of devices every time.
I’ve tried various things like unplugging/rebooting/reconnecting the devices, but that doesn’t seem to ever work. I’ve tried unplugging/rebooting the deco units; that doesn’t seem to work either.
Once the network gets in this state, the only solution I’ve been able to come up with is to use the circuit breaker in my house to shut off the power to most of the house and then incrementally flip the circuits back on to have a few devices connect at a time (starting with the circuits my Deco units are on).
I saw the recent 1.4.0 firmware update for the M5 units, so I applied that update hoping it would help the issue. No luck. I haven’t tried the 1.4.2 firmware yet (and the release notes didn’t make it seem relevant to my issue).
I got desperate the other day and decided to do a factory reset on all the Deco units. I reset them all, made minimal adjustments to the default settings, and reconnected my 60+ different devices. A day and a half later, I’m experiencing the same problems. Devices started getting disconnected (and won’t obtain IP addresses and reconnect) again.
Here’s my setup:
- Internet à 1st M9 unit which connects to 3 other decos:
- 1st M5 unit
- 2nd M5 unit
- 2nd M9 unit which connects to:
- 3rd M5 unit
- Typical load of network devices:
- ~20 TP Link brand smart switches (HS200 & HS210 models)
- ~10 TP Link brand smart plugs (various models)
- ~10 cell phones/tablets
- 4-6 laptops
- Various other smart home devices (thermostats, cameras, garage door, etc)
- Various other entertainment (smart TV’s, gaming consoles, etc)
- Deco firmware versions
- M9: 1.3.0
- M5: 1.4.0
- I have made very minimal changes from the factory default settings. Here’s what I have done:
- I do have address reservations setup for all of the smart switches/plugs plus a few other devices
- I am using the parental controls for a handful of my kids’ devices
- I turned on the antivirus options (now turned off, but doesn’t seem to matter)
When I try to look through the Deco’s logs, I see a lot of repeated messages that look like this (but with different IP addresses and static lease values):
Fri Jan 10 20:32:51 2020 daemon.err udhcpd: Sending OFFER of 192.168.68.202
Fri Jan 10 20:32:52 2020 daemon.err udhcpd: Found static lease: d344a8c0
My only guess to what’s happening is that the deco units are getting overloaded with connection requests and failing to connect any of the devices. This seems to align with my only solution (using the circuit breaker to connect a handful of devices at a time). But clearly this is not a viable long-term solution when half the network gets disconnected every other day.
If anyone has any ideas on how to fix or debug the issue, I'd love to hear them. Thanks in advance!