H3C S6850 Series Configuration Guide

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forwards only packets exactly matching the MAC-to-VLAN entries and drops inexactly matching
packets.
• As a best practice, do not configure both dynamic MAC-based VLAN assignment and the MAC
learning limit on a port.
If the two features are configured together on a port and the port learns the configured
maximum number of MAC address entries, the port processes packets as follows:
{ Forwards only packets matching the MAC address entries learnt by the port.
{ Drops unmatching packets.
• As a best practice, do not use dynamic MAC-based VLAN assignment with MSTP. In MSTP
mode, if a port is blocked in the MSTI of its target VLAN, the port drops the received packets
instead of delivering them to the CPU. As a result, the port will not be dynamically assigned to
the target VLAN.
• As a best practice, do not use dynamic MAC-based VLAN assignment with PVST. In PVST
mode, if the target VLAN of a port is not permitted on the port, the port is placed in blocked state.
The port drops the received packets instead of delivering them to the CPU. As a result, the port
will not be dynamically assigned to the target VLAN.
• As a best practice, do not configure both dynamic MAC-based VLAN assignment and automatic
voice VLAN assignment mode on a port. They can have a negative impact on each other.
Procedure
1. Enter system view.
system-view
2. Create a MAC-to-VLAN entry.
mac-vlan mac-address mac-address vlan vlan-id [ dot1p priority ]
By default, no MAC-to-VLAN entries exist.
3. Enter Layer 2 Ethernet interface view.
interface
interface-type interface-number
4. Set the port link type to hybrid.
port link-type hybrid
By default, all ports are access ports.
5. Enable the MAC-based VLAN feature.
mac-vlan enable
By default, MAC-based VLAN is disabled.
6. Enable dynamic MAC-based VLAN assignment.
mac-vlan trigger enable
By default, dynamic MAC-based VLAN assignment is disabled.
The VLAN assignment for a port is triggered only when the source MAC address of its receiving
packet exactly matches the MAC address in a MAC-to-VLAN entry.
7. (Optional.) Configure the system to assign VLANs based on the MAC address preferentially.
vlan precedence mac-vlan
By default, the system assigns VLANs based on the MAC address preferentially when both the
MAC-based VLAN and IP subnet-based VLAN are configured on a port.
8. (Optional.) Disable the port from forwarding packets that fail the exact MAC address match in its
PVID.
port pvid forbidden
By default, when a port receives packets whose source MAC addresses fail the exact match,
the port forwards them in its PVID.

H3C S6850 Series Specifications

General

Brand	H3C
Model	S6850 Series
Category	Switch
Language	English