Re: [BUG] vlan-aware bridge breaks vlan on another port on same gmac

Vladimir Oltean
2023-02-05T13:59:23Z

Hi Frank,

On Sun, Feb 05, 2023 at 02:48:55PM +0100, Frank Wunderlich wrote:
> Hi,
>
> sorry for the delay, i'm very busy recently :(
>
> noticed that i missed 2 commands ("bridge vlan add vid ..." below)
> when testing the vlan-aware bridge...now both ports are working with
> vlan-tagging...the one inside (lan0) the bridge (lanbr0) and the one
> outside (wan).
>
> BRIDGE=lanbr0
> netif=lan0
> vid=500
> #ip link add name ${BRIDGE} type bridge
> ip link add name ${BRIDGE} type bridge vlan_filtering 1 vlan_default_pvid 1
> ip link set ${BRIDGE} up
> ip link set $netif master ${BRIDGE}
> ip link set $netif up
> bridge vlan add vid $vid dev ${BRIDGE} self
> bridge vlan add vid $vid dev $netif
>
> #extract vlan from bridge to own netdev
> ip link add link ${BRIDGE} name vlan$vid type vlan id $vid
> ip a a 192.168.110.5/24 dev vlan$vid
> ip link set vlan$vid up
>
> btw can i see somehow if a bridge is vlan-aware (the flag itself)...
> "bridge vlan" command also lists non-vlan-aware bridges with vlan-id
> "1 pvid egress untagged"
>
> so vladimir your last patch works well, thx for it. you can add my tested-by when upstreaming
>
> regards Frank

Thanks for double-checking. I was wondering what could have been wrong
with the patch and just not seeing it.

You can see if a bridge is VLAN aware with "ip -d link show lanbr0".
Add "-j" to the list of arguments, and you get json output which you can
parse with jq if you need the info in a script or other program.

The software model of the Linux bridge is that where you can add, delete
and see VLANs on a bridge even if it is VLAN unaware. Those VLANs are
simply inactive until the bridge becomes VLAN aware.

I will send the patch today with your tested tag on it.