Table of Contents
Advertisement
This chapter describes how to troubleshoot your switch, primarily from a hardware perspective. You can perform
more in-depth troubleshooting on the switch using the software tools available with the switch, including the full-
featured console interface, the built-in web browser interface, and IMC (the SNMP-based network management
tool). For more information, see the chapter "Troubleshooting" in the Management and Configuration Guide for
your switch, which is on the Hewlett Packard Enterprise website at http://www.hpe.com/support/manuals.
This chapter describes the following:
•
Basic troubleshooting tips
•
Diagnosing with the LEDs
•
Proactive networking
•
Hardware diagnostic tests
•
Restoring the factory default configuration
•
Downloading new switch software
Basic troubleshooting tips
Most problems are caused by the following situations. Check for these items first when starting your
troubleshooting:
•
Connecting to devices that have a fixed full-duplex configuration: The RJ-45 ports are configured as
"Auto". That is, when connecting to attached devices, the switch will operate in one of two ways to determine
the link speed and the communication mode (half duplex or full duplex):
◦
If the connected device is also configured to Auto, the switch will automatically negotiate both link speed
and communication mode.
◦
If the connected device has a fixed configuration, for example 100 Mbps, at half or full duplex, the switch
will automatically sense the link speed, but will default to a communication mode of half duplex.
Because the switch behaves in this way (in compliance with the IEEE 802.3 standard), if a device connected to
the switch has a fixed configuration at full duplex, the device will not connect correctly to the switch. The result
will be high error rates and very inefficient communications between the switch and the device.
Make sure that all the devices connected to the switch are configured to auto negotiate, or are configured to
speed and duplex settings matching those configured on the corresponding switch port.
•
Improper network topologies: It is important to make sure you have a valid network topology. Common
topology faults include excessive cable length and excessive repeater delays between end nodes. If you have
network problems after recent changes to the network, change back to the previous topology. If you no longer
experience the problems, the new topology is probably at fault. Sample topologies are shown at the end of
chapter 2 in this book.
In addition, you should make sure that your network topology contains no data path loops. Between any two
end nodes, there should be only one active cabling path at any time. Data path loops can cause broadcast
storms that will severely impact your network performance.
Chapter 4 Troubleshooting
Chapter 4
Troubleshooting
49
Hide quick links:
Advertisement
Table of Contents
Troubleshooting
