* L3 support
-** OVN_Northbound schema
-
-*** Needs to support extra routes
-
-Currently a router port has a single route associated with it, but
-presumably we should support multiple routes. For connections from
-one router to another, this doesn't seem to matter (just put more than
-one connection between them), but for connections between a router and
-a switch it might matter because a switch has only one router port.
-
-** OVN_SB schema
-
-*** Allow output to ingress port
-
-Sometimes when a packet ingresses into a router, it has to egress the
-same port. One example is a "one-armed" router that has multiple
-routes on a single port (or in which a host is (mis)configured to send
-every IP packet to the router, e.g. due to a bad netmask). Another is
-when a router needs to send an ICMP reply to an ingressing packet.
-
-To some degree this problem is layered, because there are two
-different notions of "ingress port". The first is the OpenFlow
-ingress port, essentially a physical port identifier. This is
-implemented as part of ovs-vswitchd's OpenFlow implementation. It
-prevents a reply from being sent across the tunnel on which it
-arrived. It is questionable whether this OpenFlow feature is useful
-to OVN. (OVN already has to override it to allow a packet from one
-nested container to be forwarded to a different nested container.)
-OVS make it possible to disable this feature of OpenFlow by setting
-the OpenFlow input port field to 0. (If one does this too early, of
-course, it means that there's no way to actually match on the input
-port in the OpenFlow flow tables, but one can work around that by
-instead setting the input port just before the output action, possibly
-wrapping these actions in push/pop pairs to preserve the input port
-for later.)
-
-The second is the OVN logical ingress port, which is implemented in
-ovn-controller as part of the logical abstraction, using an OVS
-register. Dropping packets directed to the logical ingress port is
-implemented through an OpenFlow table not directly visible to the
-logical flow table. Currently this behavior can't be disabled, but
-various ways to ensure it could be implemented, e.g. the same as for
-OpenFlow by allowing the logical inport to be zeroed, or by
-introducing a new action that ignores the inport.
-
** New OVN logical actions
*** arp
the Multicast_Group table entry in ovn-sb database into
Mcast_Macs_Remote table configuration in VTEP database.
-* Use BFD as tunnel monitor.
+* Consider the use of BFD as tunnel monitor.
+
+ The use of BFD for hypervisor-to-hypervisor tunnels is probably not worth it,
+ since there's no alternative to switch to if a tunnel goes down. It could
+ make sense at a slow rate if someone does OVN monitoring system integration,
+ but not otherwise.
+
+ When OVN gets to supporting HA for gateways (see ovn/OVN-GW-HA.md), BFD is
+ likely needed as a part of that solution.
- Both ovn-controller and ovn-contorller-vtep should use BFD to
- monitor the tunnel liveness. Both ovs-vswitchd schema and
- VTEP schema supports BFD.
+ There's more commentary in this ML post:
+ http://openvswitch.org/pipermail/dev/2015-November/062385.html
* ACL
projects / cascardo / ovs.git / blobdiff