Wifi Routing Issue

[crashmepleas 10]

I've had an issue that has plagued me a while and I've never found a solution, it is starting to become annoying, I am usually able to sort out IT issues by myself.  I was hoping someone here may be able to help..

 

Please refer to the attached image so you can understand better my setup.

Basically in a nutshell any WiFi device on one side of the powerline adapter cannot see another WiFi device on the second powerline adapter.

 

So; 

Computer 1 on WiFi cant access computer 3 on WiFi.  If I plug Computer 1 into the Ethernet, (as Computer 2)  it can then access Computer 3 on Wifi

However computer 1 can access computer 4.

And Computer 2 can access computer 3 and 4.

Connecting externally via VPN, I can see Computer 3

 

For the sake of argument, Computer 3 is a Raspberry Pi with Wifi. 

Computer 1 can be either a Windows, Linux, Raspberry or android device.

Computer 1 can be either a Windows, Linux, or Raspberry device.

Computer 4 is a Raspberry Pi.

 

The router is a basic model from TalkTalk. has pretty standard features. I am running DHCP with fixed IP addresses. I have also tried a different DHCP on both the router and another computer, this didn't make a difference.

 

The powerline adapters are TPLINK AV600, one is Ethernet only, the other is dual Ethernet and WiFi (TP-LINK WPA4220 WiFi Powerline Adapter Kit - AV600)

 

 

I hope all the info is here, please ask questions, any help much appreciated.

 

 

 

[the_bloke 17]

Sounds like the issue is with firewalls or the network addresses on each device. 

 

How are you verifying they can see each other? I'd start with computer 1 and see if you can ping any of the other machines rather than relying on what you can see once in the UI.

 

Plus turn on DHCP on the router and disable any static IP addresses of the machines on the network in case the tables are all confused. Set the static addresses only when you've everything talking to one another.

 

Also, make sure the wifi is on the same IP address range as ethernet in case you've accidentally made two networks. If computer 1 on wifi can't see computer 2 on ethernet then you can discount the Powerline as being an issue (it shouldn't be anyway).

[bkcin 10]

Based on the following document - https://www.tp-link.com/uk/support/faq/1424/ 

 

There appears to be an option within the guest network settings of the TP-LINK WPA4220 WiF to "allow guests to see each other" - whilst I don't think that should cause this behaviour, depeding upon how the vendor is implementing client isolation I have seen odd behaviour in the past (with other kit at least).

 

How are you determining that they can't see each other, checking the ARP cache, pinging between devices or something else?

 

Worth checking the powerline devices are on the most recent firmware versions etc. too.

Edited December 19, 2019 by bkcin

[Ghozer 112]

My suggestion would have been like bkcin's above, check for 'Guest' network settings, as often they isolate WiFi/LAN to seperate networks (I know my router does) for security reasons... 

[crashmepleas 10]

2 hours ago, bkcin said:

Based on the following document - https://www.tp-link.com/uk/support/faq/1424/ 

 

There appears to be an option within the guest network settings of the TP-LINK WPA4220 WiF to "allow guests to see each other" - whilst I don't think that would cause this behaviour, depeding upon how the vendor is implementing client isolation I have seen odd behaviour in the past (with other kit at least).

It is worth noting that I realise I have old V1 hardware.  The above link refers to a newer hardware version.

 

2 hours ago, bkcin said:

Worth checking the powerline devices are on the most recent firmware versions etc. too.

Yeah I forgot about the firmware, I have just updated it to the latest version on the WiFi unit.

 

 

 

3 hours ago, the_bloke said:

Also, make sure the wifi is on the same IP address range as ethernet in case you've accidentally made two networks. If computer 1 on wifi can't see computer 2 on ethernet then you can discount the Powerline as being an issue (it shouldn't be anyway).

Yes they are all on the same subnet.  Also Computer 1 can see Computer 2 etc.  

 

 

 

 

I will check the other suggestions tonight thanks.

[crashmepleas 10]

 

So, I upgraded the firmware last night, as I said I have old hardware V1 and the most recent firmware was dated 2016. I didn't check what version I had previously (forgot) but after the reflash everything seems to be working as expected. I can't believe that after all this time I didn't think about checking the firmware on the powerline devices.  Thanks!

[bkcin 10]

Glad to hear it's sorted.