HP J4819A User Manual - Page 62
Improper Network Topologies., Spanning Tree Protocol, Trunking
View all HP J4819A manuals
Add to My Manuals
Save this manual to your list of manuals |
Page 62 highlights
Troubleshooting Basic Troubleshooting Tips ■ 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. 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 will cause broadcast storms that will severely impact your network performance. With your Switch 5300xl Series, if you wish to build redundant paths between important nodes in your network to provide some fault tolerance, you should enable Spanning Tree Protocol support on the switch. This ensures that only one of the redundant paths is active at any time, thus avoiding data path loops. Spanning Tree can be enabled through the switch console, the web browser interface, or ProCurve Manager. The Switch 5300xl Series also support Trunking, which allows multiple network cables to be used for a single network connection without causing a data path loop. See the Management and Configuration Guide that is on the ProCurve Web site, www.procurve.com for more information on Spanning Tree and on Trunking. ■ Connecting to devices that have a fixed full-duplex configuration. The RJ-45 ports on the Switch 5300xl Series are all 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 of half duplex Because the Switch 5300xl Series behave 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. Ensure that all devices connected to the Switch 5300xl Series are configured to auto negotiate, or are configured to connect at half duplex (all hubs are configured this way, for example). 4-2 Troubleshooting