Check Switch LEDs, Check Switch Connections

Chapter 4 Troubleshooting

Diagnosing Problems

Check Switch LEDs

If you have physical access to the switch, look at the port LEDs for troubleshooting information about the switch. See the “LEDs” section on page 1-6for a description of the LED colors and their meanings.

Check Switch Connections

Review this section when troubleshooting switch connection problems.

Bad or Damaged Cable

Always check the cable for marginal damage or failure. A cable might be just good enough to connect at the physical layer, but it could corrupt packets as a result of subtle damage to the wiring or connectors. You can identify this situation because the port has many packet errors or the port constantly flaps (loses and regains link). You should:

•Check or swap the copper or fiber-optic cable with a known, good cable.

•Look for broken or missing pins on cable connectors.

•Rule out any bad patch panel connections or media convertors between the source and destination. If possible, bypass the patch panel or eliminate faulty media convertors (fiber-optic-to-copper).

•Try the cable in another port or interface, if possible, to see if the problem follows the cable.

•Catalyst 3750-E switch StackWise cable: remove and inspect the cable and StackWise port for bent pins or damaged connectors. If the StackWise cable is bad, replace it with a known good cable.

Ethernet and Fiber Cables

Make sure that you have the correct cable type for the connection:

•For Ethernet, use Category 3 copper cable for 10 Mbps UTP connections. Use either Category 5, Category 5e, or Category 6 UTP for 10/100 or 10/100/1000 Mbps connections.

•For fiber-optic connectors, verify that you have the correct cable for the distance and port type. Make sure that the connected device ports both match and use the same type encoding, optical frequency, and fiber type. For more information about cabling, see the “10-Gigabit Ethernet X2 Transceiver Module Cable Specifications” section on page B-5and the “SFP Module Cable Specifications” section on page B-6.

•For copper connections, determine if a crossover cable was used when a straight-through was required, or the reverse. Enable auto-MDIX on the switch, or replace the cable. See the Table 2-1for recommended Ethernet cables.

Link Status

Verify that both sides have link. A single broken wire or one shutdown port can cause one side to show link, but the other side does not have link.

A link LED does not guarantee that the cable is fully functional. The cable might have encountered physical stress that causes it to function at a marginal level. If the link light for the port does not come on:

•Connect the cable from the switch to a known good device.

•Make sure that both ends of the cable are connected to the correct ports.

Catalyst 3750-E and Catalyst 3560-E Switch Hardware Installation Guide

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3750-E, 3560-E specifications

Cisco Systems RPS (Redundant Power System) 2300, along with the 3750-E and 3560-E series switches, represents a significant technological advancement in enterprise networking. These devices are designed to enhance network reliability, scalability, and efficiency, making them integral components in modern enterprise infrastructures.

The Cisco RPS 2300 is designed to provide redundant power to specified Cisco switches, ensuring continuous operation during power disruptions. This system can support up to six devices, enhancing power reliability and reducing downtime. The modularity of the RPS 2300 contributes to its flexibility, allowing enterprises to customize their power solutions to suit their networking needs. It features dual power input, which provides an additional layer of failover capability, ensuring that even in the event of a primary power failure, the backup power system can take over seamlessly.

On the other hand, the Cisco 3750-E series switches are enterprise-class devices that offer a rich feature set to support advanced network functions. These switches come with Cisco’s StackWise technology, enabling users to stack up to nine switches in a single logical unit. This increases port density and simplifies network management. The 3750-E also supports Power over Ethernet (PoE), allowing the delivery of power directly to devices like IP phones and access points through the networking cables. The switch is equipped with high-performance Layer 3 routing capabilities, providing enhanced IP routing options for enterprise networks.

The Cisco 3560-E series switches share many of the advanced features found in the 3750-E models but focus more on providing comprehensive Layer 2 and Layer 3 capabilities in a compact design. The 3560-E series supports Cisco’s advanced security features, such as dynamic VLAN assignment and security group access control lists (ACLs). Additionally, these switches support IPv6, preparing enterprise networks for future growth and addressing requirements.

Both the 3750-E and 3560-E are equipped with energy-efficient technologies, including intelligent power management and support for Energy Efficient Ethernet (EEE), helping organizations reduce their environmental footprint and operating costs. The integration of Cisco’s robust IOS software ensures that these devices are equipped with the latest features, ensuring strong performance, security, and scalability.

In summary, Cisco's RPS 2300, 3750-E, and 3560-E series exemplify the company's commitment to delivering cutting-edge networking solutions that meet the demands of modern enterprises, focusing on reliability, advanced features, and energy efficiency.

Cisco Systems 3560-E, 3750-E Check Switch LEDs, Check Switch Connections, Bad or Damaged Cable

Models: 3750-E 3560-E