Network+

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Non-unicast Packets The number of packets not directly sent from one workstation to another. For example, a broadcast packet is a non-unicast packet. The number of non-unicast packets should be smaller than the number of unicast packets. If the number of non-unicast packets is as high or higher than that of unicast packets, too many broadcast packets are being sent on your network. You should find the source of these packets and make any necessary adjustments.


Discards The number of packets that were discarded by the NIC during either transmission or reception because they weren’t assembled correctly.


Errors The number of errors that occur during transmission or reception. These numbers may indicate problems with the network card.


Unknown Protocols The number of received packets that the Windows networking stack couldn’t interpret. This statistic shows up only in the Received column, because if the computer sent them, they wouldn’t be unknown, would they?


Unfortunately, statistics don’t mean much unless they can be colored with time information. For example, if the Errors column shows 100 errors, is


that a problem? It might be if the computer has been on for only a few Copyright ©2002 SYBEX, Inc., Alameda, CA www.sybex.com


minutes. But 100 errors could be par for the course if the computer has been operating for several days. Unfortunately, the netstat utility doesn’t have a way of indicating how much time has elapsed for these statistics.


Real World Scenario




On occasion, you may need to have netstat occur every few seconds. Try placing a number after the netstat -e command, like so:

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