Thanks. As you suggested, doing a "ovs-vsctl set bridge ovs-br0 other-config:forward-bpdu=true² resolved the issue.
One thing I¹m still grappling with is what¹s written in ovs-vswitchd.conf.db(5) and the behavior I¹m seeing by setting this option to true. Namely, in http://openvswitch.org/ovs-vswitchd.conf.db.5.pdf under "other_config : forward-bpdu: optional string, either true or false², the last two sentences say "Default is disabled, set to true to enable. The following destination MAC addresss will not be forwarded when this option is enabled.² And the CDP MAC is listed: 01:00:0c:cc:cc:cc Cisco Discovery Protocol (CDP), VLAN Trunking Protocol (VTP), Dynamic Trunking Protocol (DTP), Port Aggregation Protocol (PAgP), and others So when I read this part of the doc, it seems to suggest that setting forwarding-bpdu=true should cause CDP frames not to be forwarded‹ but in reality setting this option to true enabled them to be forwarded. What am I missing? Thanks Brian On 3/30/15, 10:42 AM, "Ben Pfaff" <[email protected]> wrote: >On Sun, Mar 29, 2015 at 01:44:58PM +0000, Field, Brian wrote: >> I¹ve noticed the CDP frames are being dropped by OVS: >> >> >> # ovs-dpctl dump-flows >> >> >>skb_priority(0),in_port(2),eth(src=52:54:00:d7:50:8e,dst=01:00:0c:cc:cc:c >>c),eth_type(0/0xffff), packets:0, bytes:0, used:never, actions:drop >> >> >> >> In http://benpfaff.org/~blp/ovs-fields.pdf, it mentions ³OpenFlow and >>Open vSwitch only support LLC headers with DSAP and SSAP 0xaa and >>control byte 0x03, which indicate that a SNAP header follows the LLC >>header. In turn, OpenFlow and Open vSwitch only support a SNAP header >>with organization 0x000000." >> >> >> CDP frames use LLC/SNAP encapsulation with an organization code of >>(0xc). So it would appear this is why CDP frames are being dropped by >>OVS. > >No. I expect it's because forward-bpdu is disabled. Please see >ovs-vswitchd.conf.db(5) for details. > >> Is the limitation to only support LLC/SNAP with org values of 0x0 a >>limitation imposed on OVS because OpenFlow doesn¹t support orŠ ? > >It is true that OpenFlow does not support this, but the reason is >primarily that no one has found this important enough to implement. > >For CDP, for example, you can alternatively match on the destination >Ethernet address, which is 01:00:0c:cc:cc:cc for CDP. > _______________________________________________ discuss mailing list [email protected] http://openvswitch.org/mailman/listinfo/discuss
