nginx添加如下配置然后reload一下就好了：
worker_rlimit_nofile 655350;
worker_connections 60000; # 需要小于或等于 worker_rlimit_nofile
2019/12/14 20:24:12 [alert] 2642#2642: setrlimit(RLIMIT_NOFILE, 65535) failed (1: Operation not permitted)
setsebool -P httpd_setrlimit 1
kernel: TCP: request_sock_TCP: Possible SYN flooding on port 9000. Sending cookies. Check SNMP counters.[alert] 1319#1319: 1024 worker_connections are not enough