When tcp performs a three-way handshake, the first step is that the client sends a syn request, the server returns syn+sck, and the client responds to sck

When the syn request times out, tcp will timeout retransmission, and the number of retransmissions can be viewed here cat /proc/sys/net/ipv4/tcp_syn_retries

 You can see that the number of retransmissions is 6 

Each timeout time is 1 second, 2 seconds, 4 seconds, 8 seconds, 16 seconds, 32 seconds

Use telnet to test a non-existent ip and port 

telnet 222.222.222.222 80

 Use tcpdump to view the retransmission phenomenon

tcpdump -i any port 88

 It can be seen that after the first connection failed, it was retransmitted 6 times

The interval time is 1 second, 2 seconds, 4 seconds, 8 seconds, 16 seconds, 32 seconds

Read More:

• Error 0x80070079: The semaphore timeout period has expired
• node.js Server MySQL database connection timeout (error: connect etimeout)
• Solve Android studio connection dl.google.com Timeout problem
• Hzero – if the local swagger fails to register, the connection timeout or gateway error will be displayed
• Zookeeper connection timeout problem, and refused to connect to solve the problem
• Solution of server startup timeout in eclipse
• Get connection timeout retry: 1 MySQL errorcode 0, state 08s01 docker container accessing MySQL container is very slow and sometimes interrupted
• gerapy Run scrapy Program report timeout error [How to Solve]
• Uncaught (in promise) Error: timeout of 5000ms exceeded
• Stackexchange.redis data timeout [How to Solve]
• Lock wait timeout exceeded — transaction and index
• docker: error pulling image configuration:timeout
• [Solved] Timeout failure when upgrading horizon DAAS from 9.0.1/20.2.0 to 9.1.0/21.1.0
• MySQL error 1205 (HY000): lock wait timeout exceeded; try restarting transaction
• Vscode failed to update plug-in XHR timeout error solution
• Attempt to reset the display driver and recover from timeout failed
• Error: timeout of 5000ms exceeded error is always reported during post request
• coredns [ERROR] plugin/errors: 2 read udp : i/o timeout
• Error domain = nsurlerrordomain code = – 1001 “request timeout occurred in swift alamofire get request. ” UserInfo={NSUnderlyingErro
• Solve Linux docker pull error get https://registry-1.docker.io/v2/ : Net / http: TLS handshake timeout