Appendix A Network Troubleshooting

netstat

The netstat command line utility is used to show Ethernet statistics and current TCP/IP network connections.

Syntax: netstat

With no parameters, this command simply displays only active statistics for ports that are currently in use by one process or another.

Parameter: netstat [-a] [-e]

The -aparameter displays all available listening ports and connections whether they are active or not, while the -eparameter displays Ethernet statistics.

There are other parameters but these are the only ones you need to use for now.

The following examples show the typical output of this command:

C:\>netstat

 

 

Active Connections

 

 

Proto

Local Address

Foreign Address

State

TCP

COMPUTERA:1056

localhost:5091

ESTABLISHED

TCP

COMPUTERA:1091

localhost:27015

ESTABLISHED

TCP

COMPUTERA:1120

localhost:40000

ESTABLISHED

TCP

COMPUTERA:3243

localhost:3244

ESTABLISHED

TCP

COMPUTERA:3244

localhost:3243

ESTABLISHED

TCP

COMPUTERA:3246

localhost:3247

ESTABLISHED

TCP

COMPUTERA:3247

localhost:3246

ESTABLISHED

TCP

COMPUTERA:5091

localhost:1056

ESTABLISHED

TCP

COMPUTERA:5152

localhost:3245

CLOSE_WAIT

TCP

COMPUTERA:27015

localhost:1091

ESTABLISHED

TCP

COMPUTERA:40000

localhost:1120

ESTABLISHED

TCP

COMPUTERA:3229

172.20.0.201:http

CLOSE_WAIT

TCP

COMPUTERA:3234

172.16.1.29:1155

ESTABLISHED

TCP

COMPUTERA:3237

172.16.1.29:1155

ESTABLISHED

TCP

COMPUTERA:3240

172.16.1.29:1155

ESTABLISHED

C:\>

 

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P-870HN-51D User’s Guide