H3C S6850 Series, Руководство по настройке

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Protocols and standards
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IEEE 802.1Q, IEEE Standard for Local and Metropolitan Area Networks-Virtual Bridged Local
Area Networks
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IEEE 802.1ad, IEEE Standard for Local and Metropolitan Area Networks-Virtual Bridged Local
Area Networks-Amendment 4: Provider Bridges
Restrictions and guidelines: QinQ configuration
When you configure QinQ, follow these restrictions and guidelines:
•
The inner 802.1Q tag of QinQ frames is treated as part of the payload. As a best practice to
ensure correct transmission of QinQ frames, set the MTU to a minimum of 1504 bytes for each
port on their forwarding path. This value is the sum of the default Ethernet interface MTU (1500
bytes) and the length (4 bytes) of a VLAN tag.
•
You can use a QoS policy, a VLAN mapping, and QinQ on a port for VLAN tag manipulation. If
their settings conflict, the QoS policy has the highest priority, the VLAN mapping has the
medium priority, and QinQ has the lowest priority.
•
QinQ and two-to-two mappings are mutually exclusive. The device does not support adding an
SVLAN tag on a QinQ-enabled port and then modifying the CVLAN and SVLAN IDs.
Enabling QinQ
About enabling QinQ
Enable QinQ on customer-side ports of PEs. A QinQ-enabled port tags an incoming frame with its
PVID.
Restrictions and guidelines
Before you enable or disable QinQ on a port, you must remove any VLAN mappings on the port. For
more information about VLAN mapping, see
Layer 2—LAN Switching Configuration Guide .
Procedure
1. Enter system view.
system-view
2. Enter Layer 2 Ethernet interface view or Layer 2 aggregate interface view.
interface interface-type interface-number
3. Set the port link type.
port link-type { access | hybrid | trunk }
By default, the link type of a port is access .
4. Configure the port to allow packets from its PVID to pass through.
{
Assign the access port to the specified VLAN.
port access vlan vlan-id
By default, all access ports belong to VLAN 1.
The PVID of an access port is the VLAN to which the port belongs. The port sends packets
from the VLAN untagged.
{
Configure the hybrid port to send packets from its PVID untagged.
port hybrid vlan vlan-id-list untagged
By default, the hybrid port is an untagged member of the VLAN to which the port belongs
when its link type is access.