Count the number of Linux server connections

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we learn by TCP individual states , you can exclude and the It is helpful to locate network or system failures. View the number of connections to the server through the netstat command.

Netstat-an|awk '/tcp/{print $6} ' |sort|uniq-c 2 close_wait CLOSING established fin_wait1 Fin_wait2 4 last_ack 5 LISTEN syn_recv 295 time_wait

State	Describe
CLOSED	Without any connection
LISTENING	Listening for connection requests from a remote TCP port
Syn-sent	Application has started, open a connection
Syn-received	A connection request has arrived, waiting for confirmation
Established	Represents an open connection
Fin-wait-1	Waiting for a remote TCP connection to interrupt the request, or the acknowledgement of a previous connection interrupt request
Fin-wait-2	Waiting for connection interrupt request from remote TCP
Close-wait	Waiting for a connection interrupt request from a local user
CLOSING	Wait for the remote TCP acknowledgement of the connection interruption
Last-ack	Acknowledgement of the connection interrupt request waiting for the original send to remote TCP
Time-wait	Wait enough time to ensure that the remote TCP receives a connection interrupt request acknowledgement

1, the state of the client can be represented by the following process:

Closed->syn_sent->established->fin_wait_1->fin_wait_2->time_wait->closed

2, the status of the server can be represented by the following process:

Closed->listen->syn_received->established->close_wait->last_ack->closed

This article is from the "Concise Linux" blog, so be sure to keep this source http://easylinux.blog.51cto.com/9732761/1945539

Count the number of Linux server connections