Question Please support to solve my Wifi problems

[TillScout]

Dear forum,

Since moving into this house, I constantly have rather weird wifi problems. "Weird", because they do not seem to affect PCs and Laptops.

About my network:
My router (on the first floor) is a G-97RG6W from my vietnamese provider FPT.
After complaining to my landlord about the problems, he installed a TP-Link EC120-F5 as AP (hardwired to the router) on ground floor with a different SSID. In addition I have a TL-WA850RE range extender (but the problems already occured before installing that one). Currently my DHCP server runs on a pi-hole, this gave not improvement compared to the DHCP server running on the router.

I have around 40 devices on the network (though not all at the same time). This includes a few smarthome components (air purifiers, sockets, sensors) as well as phones and three Sonos speakers.

Now to my problems:
I have absolutely no problems with PCs and Laptops. My OpenHab Server on a Raspberry Pi perfectly communicates with all devices with low latency.
(Android) phones and tablets take a very long time to connect. Often the connection fails and the phone has to retry until it works. A lot of connections from inside apps (synchronization in games, messengers, updating weather apps...) takes ages and often does not happen at all. The phones often lose connection. Using browsers on the phones does not appear to be a problem, even when all other apps refuse synchronizing with some server, the browser still works, albeit sometimes a bit slow.

One of the Sonos speakers is hardwired to the router. In this case the speakers use their own wifi ("SonosNet"), which also appears faulty, the other speakers often disappear.

The problems are the same on all wifis, i.e. on the main router wifi, on the wifi extender, the additional AP and also on the 5GHz wifi on the main router (the rest is 2.4GHz).

Is there any way I can dig deeper into this or what I could try to narrow down the problem?

 

[Ralston18]

40 network devices - even if all are not on at the same time there is still a lot of room for errors with regards to IP addressing (Static and DHCP) along with MAC errors and subnet mask errors.

Are you using any static IP addresses? Noted an "additional AP". Any other devices?

Are those static IP addresses outside of the DHCP IP address range allowed to the router? Are Static IP addresses being reserved for any given device via the devices MAC?

Establish the "big picture".

Start by sketching out your network to show all devices.

Show each device name, its' IP address (Static or DHCP), subnet mask, MAC, connectivity (wired or wireless). Include physical wiring connections as applicable.

You may have inadvertently created a network loop.

Your router may provide some listing of connected devices and also show any that may have been connected but are apparently disconnected.

You can use nmap (zenmap) to gather network data. Either via the Command Prompt or a third party utility.

You can use "arp -a" via the Command Prompt on various computers to determine what network devices are being seen on the network by any given PC.

netsh can be very helpful with identifying wireless related problems:

https://www.webservertalk.com/netsh-wlan-commands

(Must be run from a wireless computer.)

Do the sketch first - no need to be a work of art. Just clear enough to show all devices and key information about each.

Then use the sketch and work, device by device, to determine if all is as you thought or expected.

 

[TillScout]

Thank you for the reply. I am not quite sure what you mean with the sketch. Would you like to look at it or do you suggest it as a tool for me to pin down the problem?

The thing is - I had these problems basically from day 1. We had only our phones and laptops connected. Laptops worked without a problem, phones had problems signing onto the wifi and when using other apps than browsers. So I do not think that complicated network topology or exotic devices are the reason for that.

 

[thx1138v2]

The most obvious thing about the problem is that you have moved to a new location. WiFi is simply radio and external devices, i.e. in a neighbor's house or apartment, are the most likely source of your problem. There are things you can do to minimize the interference but you may never get away from the problem no matter what you do to your equipment if the source of the interference is not under your control.

You should attach as many devices as possible to wired connections to lessen the load on your WiFi. Then look at the following article to see what kinds of solutions are available.
https://arstechnica.com/information...hat-a-deep-dive-into-why-wi-fi-kind-of-sucks/

 

[Ralston18]

The sketch is mostly for your purposes. Yes - a tool for your use and reference.

A quick way to check things when problems occur. A device "goes missing". Some new device "appears". Shares stop working. A network printer only prints for some computers.... Some device gets an automatic firmware upgrade that is faulty or reverts back to some default settings.

Getting a sense of what you have and what is there versus what you think or expect.

And I am not concerned about complicated network topology or exotic devices. What I am/would be concerned about are things as simple as typo's or one mis-configured device. End users are notorious for making changes - and not telling.....

Could well be interference per @thx1138v2: make note of the wireless frequencies and channels being used. Multiple SSIDs?

Lots of reasons to dig deeper.

[Side bar: really cannot tell for sure but the photographed D-Link router in that linked article seems to have one coiled up Ethernet cable plugged into two ports. Will concede that the photo was likely just for exhibit purposes. On the other hand those sort of connection errors do happen.]

Other people may be trying to (or have succeeded in) gaining access to your network. Someone connects in their own router. Kids frequently reset routers in hopes of being able to game more.

Use one of your wireless devices to take a look at how many wireless networks are all around you.

The "netsh" command can provide a listing.

References (and you can easily find other sources):

https://www.webservertalk.com/netsh-wlan-commands

https://www.dell.com/support/kbdoc/en-us/000141419/windows-10-using-the-wireless-network-report

 

[TillScout]

hmm, hmm, makes thinking noises

Like I said, it was from the beginning with only a little number of devices. Changing the wifi channel to the least occupied spot was the first thing I tried. In the beginning I blamed the router, but my pi-hole DHCP server did not improve things.
Compared to other homes I used to live in I think that the number of other people's wifis is rather low.

I will try to see if disconnecting or reconfiguring other devices makes a difference, but I do not have high hopes.