标签：业务 lib roo nec x86 mod libcurl serve cache
upstream hello {首先要确认服务类型是 http 还是tcp
check interval=3000 rise=2 fall=5 timeout=1000 type=http;
or
check interval=3000 rise=2 fall=5 timeout=1000 type=tcp;
然后确认健康检查的url是否支持 HEAD请求或者GET 请求
[root@100-14-1-3 ~]# curl -v -XHEAD http://hello.youbest.com/productHEAD / HTTP/1.1
User-Agent: curl/7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.27.1 zlib/1.2.3 libidn/1.18 libssh2/1.4.2
Host: baidu.com
Accept: /< HTTP/1.1 200 OK
< Date: Tue, 07 Jan 2020 08:29:28 GMT
< Server: Apache
< Last-Modified: Tue, 12 Jan 2010 13:48:00 GMT
< ETag: "51-47cf7e6ee8400"
< Accept-Ranges: bytes
< Content-Length: 81
< Cache-Control: max-age=86400
< Expires: Wed, 08 Jan 2020 08:29:28 GMT
< Connection: Keep-Alive
< Content-Type: text/html
<
以上返回表示支持 HEAD 请求 nginx 就可以这样做健康检查
check interval=3000 rise=2 fall=5 timeout=1000 type=http;
check_http_send "HEAD /product HTTP/1.0\r\n\r\n";
check_http_expect_alive http_2xx http_3xx;其中 /product 表示服务里面的埋点路径
< HTTP/1.1 200 OK 表示返回200状态
如果HEAD 请求不支持 参考下面baidu.com的GET 请求
[root@vhs100-14-1-3 ~]# curl -v -XGET http://baidu.com
GET / HTTP/1.1
User-Agent: curl/7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.27.1 zlib/1.2.3 libidn/1.18 libssh2/1.4.2
Host: baidu.com
Accept: /< HTTP/1.1 200 OK
< Date: Tue, 07 Jan 2020 08:41:38 GMT
< Server: Apache
< Last-Modified: Tue, 12 Jan 2010 13:48:00 GMT
< ETag: "51-47cf7e6ee8400"
< Accept-Ranges: bytes
< Content-Length: 81
< Cache-Control: max-age=86400
< Expires: Wed, 08 Jan 2020 08:41:38 GMT
< Connection: Keep-Alive
< Content-Type: text/html
<
<html>
<meta http-equiv="refresh" content="0;url=http://www.baidu.com/">;
</html>
以上表示支持 GET 请求 nginx 就可以这样做健康检查
check interval=3000 rise=2 fall=5 timeout=1000 type=http;
check_http_send "GET /product HTTP/1.0\r\n\r\n";
check_http_expect_alive http_2xx http_3xx;加了健康检查后，当后端有多台服务器提供服务时
Down掉的机器就不会被代理转发业务过去
从而保障业务的正常处理
标签：业务 lib roo nec x86 mod libcurl serve cache
原文地址：https://blog.51cto.com/12111640/2465021
