Dell N1100-ON, Справочное руководство

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Layer 2 Switching Commands
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VLAN Commands
Dell EMC Networking N1100-ON/N1500/N2000/N2100-
ON/N3000/N3100-ON/N4000 Series Switches
Dell EMC Networking 802.1Q VLANs are an implementation of the Virtual
Local Area Network, specification 802.1Q. Operating at Layer 2 of the OSI
model, the VLAN is a means of parsing a single network into logical user
groups or organizations as if they physically resided on a dedicated LAN
segment of their own. In reality, this virtually defined community may have
individual members scattered across a large, extended LAN. The VLAN
identifier is part of the 802.1Q tag, which is added to an Ethernet frame by an
Q-compliant switch or router. Devices recognizing 802.1Q-tagged frames
maintain appropriate tables to track VLANs. The first three bits of the
802.1Q tag are used by 802.1p to establish priority for the packet.
Dell EMC Networking switches supports 802.1Q VLANs. As such, ports may
simultaneously belong to multiple VLANs. VLANs allow a network to be
logically segmented without regard to the physical locations of devices in the
network.
Dell EMC Networking switches supports up to 4093 VLANs for forwarding.
Interfaces can be configured in trunk mode (multiple VLAN support) or
access mode (single VLAN support).
VLANs can be allocated by subnet and netmask pairs, thus allowing
overlapping subnets. For example, subnet 10.10.128.0 with Mask
255.255.128.0 and subnet 10.10.0.0 with Mask 255.255.0.0 can have different
VLAN associations.
Access, trunk and general mode VLAN configurations are maintained
independently by the switch and take affect when the interface is configured
in the relevant mode. In other words, trunk mode VLAN configuration only
affects an interface when it is configured in trunk mode. When the interface
is configured in trunk mode, access and general mode VLAN configuration is
ignored.