realtek: Traffic directly on lanX not working

[Hauke Mehrtens]

On 6/20/21 11:01 AM, Birger Koblitz wrote:
> Hi,
> 
> On 19.06.21 14:25, Hauke Mehrtens wrote:
>> Hi,
>>
>> I am unable to send and receive packets directly on the lan1 interface when it is not part of a bridge.
>>
> 
>> In wireshark on a connected host I do not see any packets from this device, but the link is up.
>>
>> When I use OpenWrt's default network configuration using a bridge, network works like expected.
>> I took care of the VLAN 100 which is used by default, but this setup does not use any VLAN.
>>
>> I would like to use a very similar configuration for the failsafe mode which is also not working correctly.
> 
> This is the same finding tmon had:
> https://forum.openwrt.org/t/support-for-rtl838x-based-managed-switches/57875/598
> 
> The reason is a hardware limitation on RTL chip families 8380-9300, they require a port to be a member of VLAN 1
> in order to send/receive traffic:
> https://forum.openwrt.org/t/support-for-rtl838x-based-managed-switches/57875/602
> 
> I am not sure how to proceed. One solution is to set this up silently in the driver, but then the existence of
> vlan 1 would be intransparent to the user, a possible security risk.
> 
> Birger
> 

Hi,

Thank you for the links, I was not aware of this strange problem.

Do you have access to a documentation of any of these chips or only some 
source code?

We could add some special handling for these chips in the failsafe mode, 
let me look into this.

Hauke