схема базы данных OVN_Southbound (OVN_Southbound database schema)
Multicast_Group TABLE
The rows in this table define multicast groups of logical ports.
Multicast groups allow a single packet transmitted over a tunnel
to a hypervisor to be delivered to multiple VMs on that
hypervisor, which uses bandwidth more efficiently.
Each row in this table defines a logical multicast group numbered
tunnel_key within datapath, whose logical ports are listed in the
ports column.
Summary:
datapath Datapath_Binding
tunnel_key integer, in range 32,768 to 65,535
name string
ports set of 1 or more weak reference to
Port_Bindings
Details:
datapath: Datapath_Binding
The logical datapath in which the multicast group resides.
tunnel_key: integer, in range 32,768 to 65,535
The value used to designate this logical egress port in
tunnel encapsulations. An index forces the key to be
unique within the datapath. The unusual range ensures that
multicast group IDs do not overlap with logical port IDs.
name: string
The logical multicast group's name. An index forces the
name to be unique within the datapath. Logical flows in
the ingress pipeline may output to the group just as for
individual logical ports, by assigning the group's name to
outport and executing an output action.
Multicast group names and logical port names share a
single namespace and thus should not overlap (but the
database schema cannot enforce this). To try to avoid
conflicts, ovn-northd uses names that begin with _MC_.
ports: set of 1 or more weak reference to Port_Bindings
The logical ports included in the multicast group. All of
these ports must be in the datapath logical datapath (but
the database schema cannot enforce this).