nginx动态负载upstream四种方案之调研篇

       项目背景：

 

        链路流程： vip —>nginx—>upstream—>server—>ip+port

 

       1.目前还没做路由功能，分组是按服务器分组(不是按用户分组)，分组发布过程一个队列形式，这里提供自定义规则切换服upstrem。

        2.不管是全量发布，分组发布，快速发布，lb只做一件事：切换upstream(running_upstream与standy_upstream

        3.动态切换LB,做法两种，一是直接操作upstream,二是操作upstream里的server. 

        4.与ci集成方式：超链接web

方案一：模块fly操作upstream,web方式增删查改upsterem里的server

       

 

 

无drop重启nginx   

 

kill -HUP `cat /data/nginx/logs/nginx.pid` 

 

#!/bin/sh 

BASE_DIR='/usr/local/' 

${BASE_DIR}nginx/sbin/nginx -t -c ${BASE_DIR}nginx/conf/nginx.
conf >& ${BASE_DIR}nginx/logs/nginx.start 

info=`cat ${BASE_DIR}nginx/logs/nginx.start` 

if [ `echo $info | grep -c "syntax is ok" ` -eq 1 ]; then 

if [ `ps aux|grep "nginx"|grep -c "master"` == 1 ]; then 

kill -HUP `cat ${BASE_DIR}nginx/logs/nginx.pid` 

echo "ok" 

else 

killall -9 nginx 

sleep 1 

${BASE_DIR}nginx/sbin/nginx 

fi 

else 

echo "######## error: ########" 

cat ${BASE_DIR}nginx/logs/nginx.start 

fi 

 

reference:

 

 

方案二：模块ngx_dynamic_upstream,api+python方式(直接操作upstream里的server)

 

因为api接口操作不是太直观，在django上以web方式增删查改upstream  

 

HTTP APIs

You can operate upstreams dynamically with HTTP APIs.

list

$ curl "http://127.0.0.1:6000/dynamic?upstream=zone_for_backends"
server 127.0.0.1:6001;
server 127.0.0.1:6002;
server 127.0.0.1:6003;
$

verbose

$ curl "http://127.0.0.1:6000/dynamic?upstream=zone_for_backends&verbose="
server 127.0.0.1:6001 weight=1 max_fails=1 fail_timeout=10;
server 127.0.0.1:6002 weight=1 max_fails=1 fail_timeout=10;
server 127.0.0.1:6003 weight=1 max_fails=1 fail_timeout=10;
$

update_parameters

$ curl "http://127.0.0.1:6000/dynamic?upstream=zone_for_backends&server=127.0.0.1:6003&weight=10&max_fails=5&fail_timeout=5"
server 127.0.0.1:6001 weight=1 max_fails=1 fail_timeout=10;
server 127.0.0.1:6002 weight=1 max_fails=1 fail_timeout=10;
server 127.0.0.1:6003 weight=10 max_fails=5 fail_timeout=5;
$

The supported parameters are blow.

• weight
• max_fails
• fail_timeout

down

$ curl "http://127.0.0.1:6000/dynamic?upstream=zone_for_backends&server=127.0.0.1:6003&down="
server 127.0.0.1:6001 weight=1 max_fails=1 fail_timeout=10;
server 127.0.0.1:6002 weight=1 max_fails=1 fail_timeout=10;
server 127.0.0.1:6003 weight=1 max_fails=1 fail_timeout=10 down;
$

up

$ curl "http://127.0.0.1:6000/dynamic?upstream=zone_for_backends&server=127.0.0.1:6003&up="
server 127.0.0.1:6001 weight=1 max_fails=1 fail_timeout=10;
server 127.0.0.1:6002 weight=1 max_fails=1 fail_timeout=10;
server 127.0.0.1:6003 weight=1 max_fails=1 fail_timeout=10;
$

add

$ curl "http://127.0.0.1:6000/dynamic?upstream=zone_for_backends&add=&server=127.0.0.1:6004"
server 127.0.0.1:6001;
server 127.0.0.1:6002;
server 127.0.0.1:6003;
server 127.0.0.1:6004;
$

remove

$ curl " http://127.0.0.1:6000/dynamic?upstream=zone_for_backends&remove=&server=127.0.0.1:6003"
server 127.0.0.1:6001;
server 127.0.0.1:6002;
server 127.0.0.1:6004;

 

reference:

https://github.com/cubicdaiya/ngx_dynamic_upstream

 

 

 

 

 

方案三：lua(lua_code_cache)热装载＋upstream ,直接操作upstream

 

简说热装载(热加载) ：lua代码产生变更，利用lua_code_cache on ，实现自动加载，不用reload nginx。

亮点： 通过lua处理,不用重启nginx，利用api进行增删查改

不足：操作还是基于命令方式，后期还得加上web操作

 

restful interface

GET

• /detail get all upstreams and their servers
• /list get the list of upstreams
• /upstream/name find the upstream by it's name

POST

• /upstream/name update one upstream
• body commands;
• body server ip:port;

DELETE

• /upstream/name delete one upstream

Call the interface, when you get the return code is HTTP_INTERNAL_SERVER_ERROR 500, you need to reload nginx to make the Nginx work at a good state.

If you got HTTP_CONFLICT 409, you need resend the same commands again latter.

The /list and /detail interface will return HTTP_NO_CONTENT 204 when there is no upstream.

Other code means you should modify your commands and call the interface again.

ATTENEION: You also need a third-party to generate the new config and dump it to Nginx'conf directory.

Sample

» curl -H "host: dyhost" 127.0.0.1:8080



502 Bad Gateway
nginx/1.3.13



» curl -d "server 127.0.0.1:8089;server 127.0.0.1:8088;" 127.0.0.1:8081/upstream/dyhost
success

» curl -H "host: dyhost" 127.0.0.1:8080
8089

» curl -H "host: dyhost" 127.0.0.1:8080
8088

» curl 127.0.0.1:8081/detail
host1
server 127.0.0.1:8088

host2
server 127.0.0.1:8089

dyhost
server 127.0.0.1:8089
server 127.0.0.1:8088

» curl -i -X DELETE 127.0.0.1:8081/upstream/dyhost
success

» curl 127.0.0.1:8081/detail
host1
server 127.0.0.1:8088

host2
server 127.0.0.1:8089

API

extern ngx_flag_t ngx_http_dyups_api_enable;
ngx_int_t ngx_dyups_update_upstream(ngx_str_t *name, ngx_buf_t *buf,
    ngx_str_t *rv);
ngx_int_t ngx_dyups_delete_upstream(ngx_str_t *name, ngx_str_t *rv);

extern ngx_dyups_add_upstream_filter_pt ngx_dyups_add_upstream_top_filter;
extern ngx_dyups_del_upstream_filter_pt ngx_dyups_del_upstream_top_filter;

Lua API Example

NOTICE: you should add the directive dyups_interface into your config file to active this feature

content_by_lua '
    local dyups = require "ngx.dyups"

    local status, rv = dyups.update("test", [[server 127.0.0.1:8088;]]);
    ngx.print(status, rv)
    if status ~= ngx.HTTP_OK then
        ngx.print(status, rv)
        return
    end
    ngx.print("update success")

    status, rv = dyups.delete("test")
    if status ~= ngx.HTTP_OK then
        ngx.print(status, rv)
        return
    end
    ngx.print("delete success")

';

 

reference:

https://github.com/yzprofile/ngx_http_dyups_module

https://github.com/moonbingbing/openresty-best-practices/blob/master/ngx_lua/hot_load.md

 

方案四：自研

      自已写lua+redis，再封装一层api，供业务插入标签，再进行增删查改