May 2006
Intermediate to advanced
480 pages
12h 20m
English
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9.4 Determining the Connection State
You can list all the actual TCP and UDP connections using the netstat command with the — a parameter.
$ netstat -an
Active Internet connections (including servers) Proto Recv-Q Send-Q Local Address Foreign Address (state) tcp 0 0 194.149.105.18.22 194.149.103.204.24695 TIME_WAIT tcp 0 0 194.149.105.18.3099 194.108.145.128.25 SYN_SENT tcp 0 34472 194.149.105.18.3079 195.47.32.245.25 ESTABLISHED tcp 0 0 *.22 *.* LISTEN tcp 0 0 *.25 *.* LISTEN tcp 0 0 *.53 *.* LISTEN udp 0 0 *.53 *.* udp 0 0 127.0.0.1.53 *.*
Note
If the switch — n is used, it means that the IP addresses will not be replaced with DNS names by reverse transltion.
The first two lines are the list header. The columns have the following meanings: ...
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