Posted: Sun Aug 14, 2022 5:51 Post subject: Ancient router (TL-WR841N) - switch isolates the devices.
Hello everyone,
I have an old TL-WR841N here as a backup if the internet is down.
It establishes an connection using client mode by connecting to a smartphone hotspot.
It works fine, except for one thing:
The devices on the 4-port switch of the TP-Link cannot communicate with each other.
On the other hand, if I connect a device to the WAN port, it can be pinged from and to the others, but only this one device.
This behavior is independent of whether the device is operated in client, client bridge or ap mode.
Interestingly, while the router is booting, pings go "through" for a very short time, but then the devices are isolated.
Is it possible to configure it somehow?
And then a second question:
Unfortunately, the option to enable the DHCP server is hidden when activating the client bridge.
Is there a way to enable the it anyway?
You need to enable VLAN on the switch ports, you get "destination unreachable" between LAN ports unless its not enabled on that specific hardware.
known working fix for TP-Link (WR84x and WR94x models):
-> goto Administration - Commands, enter/copy the 3 following commands into the Commands box:
swconfig dev switch0 set reset 1
swconfig dev switch0 set enable_vlan 1
swconfig dev switch0 set apply
Select "Save Startup" button and reboot device.
If you don't need it, you should disable WAN port if LAN <> LAN ping is working (uplink from a LAN port should work). This will reduce unnessesary load on the CPU because the WAN port is part of the MAiN chip, the LAn are on a dedicated switch chip.
The only thing I would suggest, is saving the commands as Firewall, this way it will survive reboots...
With "Save Startup" the commands are executed on reboot, off/on cycle on my WR941v6 with r40750. Should be same with other/newer builds if not broken.
Any response from mfessler may help.
Beside that the android hotspot should be able to handle 5-10 connections, assume this limits any repeated Wifi connection linked with that hotspot. Never tried that because the wifi hotspot speed from the android device may limit the usablity/amount of connected devices.