近来几天发现访问博客端文章间歇性报出 502,一开始以为是 solo 博客端的配置问题,纠正排查后发现不是博客后台设置的问题。后来查看 nginx 的日志。发现如下报错: 2019/10/20 20:05:09 [error] 8539#0: *67 no live upstreams while connecting to upstream, client: 111.194.50.93, server: cjzshilong.cn, request: "GET /sw.js HTTP/1.1", upstream: "http://localhost/sw.js", host: "www.cjzshilong.cn", referrer: "www.cjzshilong.cn/sw.js" 2019/10/20 20:08:53 [notice] 8638#0: signal process started 2019/10/20 20:09:11 [error] 8659#0: *2 upstream sent too big header while reading resp....