Cisco Catalyst 2960 Series, Руководство по настройке

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On using the LAN Base image, only the lanbase-default template supports 1000 VLANs.
The remaining templates (default and lanbase-routing) only supports 255 VLANs. Up
to 64 VLANs are supported when the switch is running the LAN Lite image. Note
• The switch supports homogeneous stacking and mixed stacking. Mixed stacking is supported only with
the Catalyst 2960-S switches. A homogenous stack can have up to eight stack members, while a mixed
stack can have up to four stack members. All switches in a switch stack must be running the LAN Base
image.
Restrictions for VLANs
The following are restrictions for configuring VLANs:
• 1K VLAN is supported only on switches running the LAN Base image with the lanbase-default template
set.
• To avoid warning messages of high CPU utilization with a normal-range VLAN configuration, we
recommend that you have no more than 256 VLANs. In such cases, approximately 10 access interfaces
or 5 trunk interfaces can flap simultaneously with negligible impact to CPU utilization (if there are more
interfaces that flap simultaneously, then CPU usage may be excessively high.)
Information About VLANs
Logical Networks
A VLAN is a switched network that is logically segmented by function, project team, or application, without
regard to the physical locations of the users. VLANs have the same attributes as physical LANs, but you can
group end stations even if they are not physically located on the same LAN segment. Any switch port can
belong to a VLAN, and unicast, broadcast, and multicast packets are forwarded and flooded only to end
stations in the VLAN. Each VLAN is considered a logical network, and packets destined for stations that do
not belong to the VLAN must be forwarded through a router or a switch supporting fallback bridging. In a
switch stack, VLANs can be formed with ports across the stack. Because a VLAN is considered a separate
logical network, it contains its own bridge Management Information Base (MIB) information and can support
its own implementation of spanning tree.
VLANs are often associated with IP subnetworks. For example, all the end stations in a particular IP subnet
belong to the same VLAN. Interface VLAN membership on the switch is assigned manually on an
interface-by-interface basis. When you assign switch interfaces to VLANs by using this method, it is known
as interface-based, or static, VLAN membership.
Traffic between VLANs must be routed.
The switch can route traffic between VLANs by using switch virtual interfaces (SVIs). An SVI must be
explicitly configured and assigned an IP address to route traffic between VLANs.
Consolidated Platform Configuration Guide, Cisco IOS Release 15.2(4)E (Catalyst 2960-X Switches)
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Restrictions for VLANs