查看nginx error log

2019/08/06 10:50:21 [crit] 18144#0: *136 mkdir() "/usr/local/nginx/proxy_temp/7/02" failed (13: Permission denied) while reading upstream, client: 192.168.4.157, server: jianeryou.jiandan100.cn, request: "GET /js/vendorLibs-1804261126.js HTTP/1.1", upstream: "http://127.0.0.1:8300/js/vendorLibs-1804261126.js", host: "jianeryou.jiandan100.cn", referrer: "https://jianeryou.jiandan100.cn/teacherLogin"

把mkdir失败的目录改为 跟nginx运行的用户一样

sudo chown -hR www-data:www-data /usr/local/nginx/proxy_temp