Cisco Systems Catalyst 2955 manual Overview Front-Panel Description

Models: Catalyst 2955

1 298
Download 298 pages 1.32 Kb
Page 53
Image 53

Chapter 2 Overview

Front-Panel Description

The connector is a pluggable-screw terminal block connector that provides power and return connections for both the primary and secondary power supplies. The positive DC power connection for power supply A is labeled VA, and the return for power supply A is the adjacent connection labeled RT. For power supply B (the redundant power supply), the positive DC power connection is labeled VB, and the return is the adjacent connection labeled RT.

The Catalyst 2955 switch can operate with a single power supply or with dual power supplies. In dual-power mode, the switch draws power from the power supply with higher voltage. If the primary power supply fails in dual-power mode, the alternate power supply gives power to the switch.

Warning When you connect or disconnect the power and relay connector with power applied, an electrical arc can occur. This could cause an explosion in hazardous area installations. Be sure that power is removed from the switch and alarm circuit. Be sure that power cannot be accidentally turned on or verify that the area is nonhazardous before proceeding.

Failure to securely tighten the power and relay connector captive screws can result in an electrical arc if the connector is accidentally removed. Statement 1058

The power and relay connector provides an interface for two independent, normally open (NO) alarm relays. The relays can be triggered by alarms for environmental, power supply, and port status conditions. The relays can be configured to send a fault signal to an external alarm device, such as a bell or a light indicator. You can use the CLI to associate any alarm condition with a single alarm relay or with both relays.

To connect an external alarm device to the relay, you must connect two relay contact wires to complete an electrical circuit. Because each external alarm device requires two connections to a relay, the Catalyst 2955 switch supports a maximum of two external alarm devices.

Note See the switch configuration guide for instructions on how to configure the alarm relays.

For more information about the power and relay connector, see Appendix B, “Connectors and Cables.”

 

 

Catalyst 2955 Hardware Installation Guide

 

 

 

 

 

 

78-14944-03

 

 

2-9

 

 

 

Page 53
Image 53
Cisco Systems Catalyst 2955 manual Overview Front-Panel Description

Catalyst 2955 specifications

The Cisco Systems Catalyst 2955 is a robust and versatile Ethernet switch designed for enterprises seeking reliable Layer 2 switching capabilities. Known for its steadfast performance and extensive feature set, the Catalyst 2955 is particularly favored for environments requiring high-density connectivity and advanced traffic management.

One of the hallmark features of the Catalyst 2955 is its support for IEEE 802.1Q VLAN tagging, which allows for efficient traffic segregation and helps improve network security. The switch can handle up to 256 virtual LANs, supporting a more organized network structure and optimized resource allocation. This VLAN capability is crucial for businesses that need to segment their networks for various departments or applications while maintaining efficient communication between them.

The Catalyst 2955 is equipped with a comprehensive Quality of Service (QoS) mechanism, which prioritizes critical applications and ensures that voice, video, and data traffic receive appropriate bandwidth. By providing features such as classification, marking, queuing, and congestion avoidance, the switch helps meet the demands of real-time applications, thereby enhancing user experience and productivity.

Another remarkable technology integrated into the Catalyst 2955 is Spanning Tree Protocol (STP), which prevents loops in redundant network connections. Enhanced with features like Rapid Spanning Tree Protocol (RSTP), this switch minimizes downtime by allowing for quicker convergence times in case of topology changes. The ability to support both STP and RSTP is vital for maintaining network stability and performance.

The Catalyst 2955 is also designed with network management and monitoring in mind. It includes features like Simple Network Management Protocol (SNMP), which enables administrators to manage network resources effectively and troubleshoot issues more efficiently. With support for Cisco’s proprietary software, it offers insights into traffic patterns and usage statistics that can aid in maintaining optimal network health.

Physical characteristics of the Catalyst 2955 include various configurations with either 24 or 48 ports, suitable for different deployment scenarios. The switch is designed for rack mounting, making it an ideal solution for data centers and enterprise networks where space is a consideration.

In summary, the Cisco Systems Catalyst 2955 stands out for its solid Layer 2 functionality, VLAN support, QoS capabilities, network stability features such as STP, and extensive management tools, making it an excellent choice for organizations aiming to enhance network resiliency and performance. Its balance of performance and manageability continues to make it a viable option in the competitive landscape of networking equipment.