java - tcp connection exception, please help analyze the reason

Question

netstat -antp|grep 8091
After the server has been running for a period of time, suddenly all tcp cannot connect normally. Check the information as follows

Help analyze the reason, thank you
The system uses Tencent Cloud's centos6.5 64-bit virtual machine, and a tomcat server is built on it. This abnormality will occur within two days of the average running period, and then the client Can't connect.
netstat -antp|grep 8091|wc -l
155
cat /proc/sys/net/ipv4/tcp_max_syn_backlog
512
can only restart tomcat, after restarting it is as follows

Answer 1

I didn’t see anything abnormal there

Answer 2

The questioner did not clarify whether "tcp cannot connect normally" is the server or the client. Judging from the screenshot, it is using a machine to continuously connect to the server. You can check whether there is a large number of TIME_WAIT in the client part of netstat
If so , the client uses a tcp short connection. After close, if REUSE is not configured, the client machine will no longer be able to use the same port within 2msl.