QTECH QSW-8300 Инструкция по настройке - Manual (Page 123)

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Chapter 16 Layer 3 Forward Configuration
Switch supports Layer 3 forwarding which forwards Layer 3 protocol packets (IP packets)
across VLANs. Such forwarding uses IP addresses, when a interface receives an IP packet, it
will perform a lookup in its own routing table and decide the operation according to the lookup
result. If the IP packet is destined to another subnet reachable from this switch, then the
packet will be forwarded to the appropriate interface. Switch can forward IP packets by
hardware, the forwarding chip of switch have a host route table and default route table. Host
route table stores host routes to connect to the switch directly; default route table stores
network routes (after aggregation algorithm process).
If the route (either host route or network route) for forwarding unicast traffic exists in the
forwarding chip, the forwarding of traffic will be completely handled by hardware. As a result,
forwarding efficiency can be greatly improved, even to wire speed.
16.1 Layer 3 Interface
16.1.1 Introduction to Layer 3 Interface
Layer 3 interface can be created on switch. The Layer 3 interface is not a physical interface
but a virtual interface. Layer 3 interface is built on VLANs. The Layer 3 interface can contain
one or more layer 2 ports which belong to the same VLAN, or contain no layer 2 ports. At least
one of the Layer 2 ports contained in Layer 3 interface should be in UP state for Layer 3
interface in UP state, otherwise, Layer 3 interface will be in DOWN state. All layer 3 interfaces
in the switch use the same MAC address by default, this address is selected from the reserved
MAC address while creating Layer 3 interface. The Layer 3 interface is the base for layer 3
protocols. The switch can use the IP addresses set in the layer 3 interfaces to communicate
with the other devices via IP. The switch can forward IP packets between different Layer 3
interfaces. Loopback interface belongs to Layer 3 interface.
16.1.2 Layer 3 Interface Configuration Task List
Layer 3 Interface Configuration Task List:
1. Create Layer 3 interface
2. Bandwidth for Layer 3 Interface configuration
3. Configure VLAN interface description
4. Open or close the VLAN interface
5. VRF configuration
(1) Create VRF instance and enter VPN view
(2) Configure RD of VRF instance (optional)
(3) Configure RT of VRF instance (optional)