Cisco Systems 3560 Manual De Usuario
1-7
Catalyst 3560 Switch Software Configuration Guide
OL-8553-06
Chapter 1 Overview
Features
Availability and Redundancy Features
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HSRP for command switch and Layer 3 router redundancy
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Enhanced object tracking, which separates the tracking mechanism from HSRP and creates a
separate, standalone tracking process that can be used by processes other than HSRP
separate, standalone tracking process that can be used by processes other than HSRP
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UniDirectional Link Detection (UDLD) and aggressive UDLD for detecting and disabling
unidirectional links on fiber-optic interfaces caused by incorrect fiber-optic wiring or port faults
unidirectional links on fiber-optic interfaces caused by incorrect fiber-optic wiring or port faults
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IEEE 802.1D Spanning Tree Protocol (STP) for redundant backbone connections and loop-free
networks. STP has these features:
networks. STP has these features:
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Up to 128 spanning-tree instances supported
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Per-VLAN spanning-tree plus (PVST+) for load balancing across VLANs
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Rapid PVST+ for load balancing across VLANs and providing rapid convergence of
spanning-tree instances
spanning-tree instances
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UplinkFast and BackboneFast for fast convergence after a spanning-tree topology change and
for achieving load balancing between redundant uplinks, including Gigabit uplinks
for achieving load balancing between redundant uplinks, including Gigabit uplinks
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IEEE 802.1s Multiple Spanning Tree Protocol (MSTP) for grouping VLANs into a spanning-tree
instance and for providing multiple forwarding paths for data traffic and load balancing and rapid
per-VLAN Spanning-Tree plus (rapid-PVST+) based on the IEEE 802.1w Rapid Spanning Tree
Protocol (RSTP) for rapid convergence of the spanning tree by immediately changing root and
designated ports to the forwarding state
instance and for providing multiple forwarding paths for data traffic and load balancing and rapid
per-VLAN Spanning-Tree plus (rapid-PVST+) based on the IEEE 802.1w Rapid Spanning Tree
Protocol (RSTP) for rapid convergence of the spanning tree by immediately changing root and
designated ports to the forwarding state
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Optional spanning-tree features available in PVST+, rapid-PVST+, and MSTP mode:
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Port Fast for eliminating the forwarding delay by enabling a port to immediately change from
the blocking state to the forwarding state
the blocking state to the forwarding state
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BPDU guard for shutting down Port Fast-enabled ports that receive bridge protocol data units
(BPDUs)
(BPDUs)
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BPDU filtering for preventing a Port Fast-enabled port from sending or receiving BPDUs
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Root guard for preventing switches outside the network core from becoming the spanning-tree
root
root
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Loop guard for preventing alternate or root ports from becoming designated ports because of a
failure that leads to a unidirectional link
failure that leads to a unidirectional link
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Equal-cost routing for link-level and switch-level redundancy
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Flex Link Layer 2 interfaces to back up one another as an alternative to STP for basic link
redundancy
redundancy
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Link-state tracking to mirror the state of the ports that carry upstream traffic from connected hosts
and servers, and to allow the failover of the server traffic to an operational link on another Cisco
Ethernet switch.
and servers, and to allow the failover of the server traffic to an operational link on another Cisco
Ethernet switch.
VLAN Features
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Support for up to 1005 VLANs for assigning users to VLANs associated with appropriate network
resources, traffic patterns, and bandwidth
resources, traffic patterns, and bandwidth
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Support for VLAN IDs in the 1 to 4094 range as allowed by the IEEE 802.1Q standard
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VLAN Query Protocol (VQP) for dynamic VLAN membership