[ovs-discuss] STP on Ryu controller using Open vSwitch 2.4

[Alessio Giorgetti]

Dear Ben,

thank you a lot for your suggestions... I just set the 
forward-bpdu="true" in the bridge using the command:

 > ovs-vsctl set bridge br0 other-config:forward-bpdu=true

and this is now correctly configured... however the system is still not 
working. It seems that bpdu frames are still discarded.

I see there are two options in the mod-port command...

- stp / no-stp
- receive-stp / no-receive-stp

These are currently set to the default values. STP is not enabled on the 
switch. How should I set these parameters just to enable reception of 
STP frames and OpenFlow processing of them?

Best Regards,
alessio

This are currently set to the default values.
Il 13/05/2016 17:11, Ben Pfaff ha scritto:
> On Fri, May 13, 2016 at 02:34:34PM +0200, Alessio Giorgetti wrote:
>> I'm trying to use the Ryu controller on a very simple network composed of
>> five Open vSwitch 2.4 (no loop is present currently in the topology).
>>
>> I would enable STP at the controller, so followed the indications found on
>> the ryubook and changed the BPDU dest address to 01:80:c2:00:00:0e, as
>> illustrated in simple_switch_stp_13. This is because otherwise Open
>> vSwitches with not enabled STP discards frames addressed to
>> 01:80:c2:00:00:00.
>>
>> However, the system is not working, from the ryu output it seems that STP is
>> not converging and several LinkUp/LinkDown events are detected.
>>
>> I simplified the network topology keeping only 2 switches, connected by a
>> single link but the problem persists.
>>
>> I guess it is a configuration problem of the switches, it seems that also
>> frames addressed to 01:80:c2:00:00:0e are discarded.
>
> Of course they are, it's required by the IEEE specification for
> switches, see the documentation:
>
>         other_config : forward-bpdu: optional string, either true or false
>                Controls forwarding of BPDUs and other  network  control  frames
>                when  NORMAL  action  is  invoked.  When this option is false or
>                unset, frames with reserved Ethernet addresses (see table below)
>                will  not  be  forwarded.  When this option is true, such frames
>                will not be treated specially.
>
>                The above general rule has the following exceptions:
>
>                ·      If STP is enabled on the bridge (see the stp_enable  col‐
>                       umn  in  the  Bridge  table),  the  bridge  processes all
>                       received STP packets and never passes them to OpenFlow or
>                       forwards  them.   This is true even if STP is disabled on
>                       an individual port.
>
>                ·      If LLDP is enabled on an interface (see the  lldp  column
>                       in the Interface table), the interface processes received
>                       LLDP packets and never passes them to  OpenFlow  or  for‐
>                       wards them.
>
>                Set this option to true if the Open vSwitch bridge connects dif‐
>                ferent Ethernet networks and is not configured to participate in
>                STP.
>
>                This  option  affects packets with the following destination MAC
>                addresses:
>
>                01:80:c2:00:00:00
>                       IEEE 802.1D Spanning Tree Protocol (STP).
>
>                01:80:c2:00:00:01
>                       IEEE Pause frame.
>
>                01:80:c2:00:00:0x
>                       Other reserved protocols.
>
>                00:e0:2b:00:00:00
>                       Extreme Discovery Protocol (EDP).
>
>                00:e0:2b:00:00:04 and 00:e0:2b:00:00:06
>                       Ethernet Automatic Protection Switching (EAPS).
>
>                01:00:0c:cc:cc:cc
>                       Cisco Discovery Protocol (CDP),  VLAN  Trunking  Protocol
>                       (VTP),  Dynamic Trunking Protocol (DTP), Port Aggregation
>                       Protocol (PAgP), and others.
>
>                01:00:0c:cc:cc:cd
>                       Cisco Shared Spanning Tree Protocol PVSTP+.
>
>                01:00:0c:cd:cd:cd
>                       Cisco STP Uplink Fast.
>
>                01:00:0c:00:00:00
>                       Cisco Inter Switch Link.
>
>                01:00:0c:cc:cc:cx
>                       Cisco CFM.
>