Use the Port Statistics window to display the statistics for data sent (transmitted) and received by the switch ports since the switch was last powered on, was restarted, or since the statistics were last cleared. The types of statistics collected and displayed are grouped under these tabs: Tips on using this window: - Use the Port Statistics window with the graphs and gauges on the Dashboard and the Trends window.
- Click the column headings to sort information.
- Click
Refresh on the toolbar to update the information. The information on this window is automatically updated at each system refresh (every 60 seconds). - To understand the complete state of the ports, use this window with:
- Packet Error gauge on the Dashboard
- Port Utilization graph on the Dashboard
- Trends window
- Port Status window
Back to the top Note: Clearing the statistics on one tab clears the statistics on the other tabs. To clear the statistics for a specific port: - Select one or more ports.
- Click Clear Counters.
To cancel any selections in the Clear column, click Cancel. Back to the top The Overview tab displays: - The total number of bytes sent and received on each port.
- The total number of packets sent and received on each port.
- The total number of error packets sent. This includes total collisions, late collisions, and excessive collisions.
- The total number of error packets received. This includes frame check sequence (FCS) and alignment errors. Equipment being powered on or off can cause FCS and alignment errors.
This tab displays the specific numbers of error packets received on and sent from the port, which is a granularity that is not available from the Dashboard and Trends graphs. The number of error packets can mean a duplex mismatch, incompatibilities with the port and its attached device, or faulty cables or attached devices. Any of these problems can cause slow network performance, data loss, or lack of connectivity. For example, to troubleshoot problems regarding loss of connectivity, clear the statistics for the port in question, and see if the port continues to receive and send packets. Note: Clearing the statistics on this tab clears the statistics on the other tabs. You can sort the lists by clicking the column headings. Column | Explanation | Port | The number of the port, including the port type (such as Fa for Fast Ethernet and Gi for Gigabit Ethernet) and the port number. | Transmitted bytes | The total number of bytes sent from each port. | Total transmitted packets | The total number of packets sent from each port. This includes unicast, multicast, and broadcast packets. | Received bytes | The total number of bytes received on each port. | Total received packets | The total number of packets received on each port. This includes well-formed unicast, multicast, and broadcast packets. | Total transmit error packets | The total number of error packets sent. This includes total runts, collisions, late collisions, and excessive collisions. | Total receive error packets
| The total number of error packets received. This includes runts, and FCS and alignment errors. | Back to the top Note: Clearing the statistics on this tab clears the statistics on the other tabs. The Transmit Detail tab displays: - Transmitted unicast, multicast, and broadcast packets on each port
- Detailed statistics of errors sent to each port
You can use the statistics on this tab to troubleshoot unusual changes in network traffic. If a port is sending an unusually high amount of traffic (such as multicast or broadcast packets), check the connected device to see if this traffic pattern is normal or could mean a problem. You can sort the lists by clicking the column headings. Column | Explanation | Port | The number of the port, including the port type (such as Fa for Fast Ethernet and Gi for Gigabit Ethernet) and the port number. | Unicast packets | The total number of well-formed unicast packets sent by a port. It excludes packets sent with errors or with multicast or broadcast destination addresses. | Multicast packets | The total number of well-formed multicast packets sent by a port. It excludes packets sent with errors or with unicast or broadcast destination addresses. | Broadcast packets | The total number of well-formed broadcast packets sent by a port. It excludes packets sent with errors or with unicast or multicast destination addresses. | Total collision packets | The total number of packets sent without error after having 1 to 15 collisions. It includes packets of all destination address types and excludes packets discarded because of insufficient resources or late collisions. | Excessive collision packets | The total number of packets that were not sent after 16 collisions. It includes packets of all destination address types. | Late collision packets | The total number of packets discarded because of late collisions detected during transmission. It includes all sent packets that had a collision after the transmission of the packet sixty-fourth byte. The preamble and start frame delimiter (SFD) are not included in the frame byte count. | Back to the top Note: Clearing the statistics on this tab clears the statistics on the other tabs. The Receive Detail tab displays: - Received unicast, multicast, and broadcast packets on each port.
- Detailed statistics of receive errors on each port.
You can use the statistics on this tab to troubleshoot unusual changes in network traffic. If a port is receiving an unusually high amount of traffic (such as multicast or broadcast packets), check the connected device to see if this traffic pattern is normal for the connected device or could mean a problem. You can sort the lists by clicking the column headings. Column | Explanation | Port | The number of the port, including the port type (such as Fa for Fast Ethernet and Gi for Gigabit Ethernet) and the port number. | Unicast packets | The total number of well-formed unicast packets received by a port. It excludes packets received with errors, with multicast or broadcast destination addresses, or undersize packets, discarded packets, or those without a destination. | Multicast packets | The total number of well-formed multicast packets received by a port. It excludes packets received with errors, with unicast or broadcast destination addresses, with oversized or undersize packets, discarded packets, or those without a destination. | Broadcast packets | The total number of well-formed broadcast packets received by a port. It excludes packets received with errors, with unicast or multicast destination addresses, or with oversized or undersize packets, discarded packets, or those without a destination. | FCS error packets | The total number of packets received with FCS errors. It excludes undersized packets with FCS errors. | Alignment errors packets | The total number of packets received with alignment errors. It includes all the packets received with both an FCS error and a nonintegral number of bytes. | Oversize packets | The total number of received packets with more than 1518 bytes that had both good and bad FCS values. | Undersize packets | The total number of received packets that were smaller than 64 octets long and were otherwise well-formed. | Collision fragments | The total number of frames smaller than 64 bytes that have an integral number of bytes and bad FCS values. | Back to the top |