nginx connect()错误(10061: No connection could be made because the target machine actively refused it)

nginx偶尔会报下面这个错误：

2019/05/20 10:54:56 [error] 717920#661892: *16943633 connect() failed (10061: No connection could be made because the target machine actively refused it) while connecting to upstream, client: 123.180.56.166, server: , request: "GET /reg/viewbalance HTTP/1.1", upstream: "http://[::1]:9997/reg/viewbalance", host: "www.xxxxxxx.xx:9998", referrer: "http://www.xxxxxxx.xx:9998/reg/main"

经搜索资料发现，需要将配置文件中的localhost或127.0.0.1改为192.168.1.100即可解决。