背景介紹

上篇介紹了利用Nginx反向代理實(shí)現(xiàn)負(fù)載均衡，本文詳細(xì)講述Nginx下的幾種負(fù)載均衡策略。

輪詢

輪詢，顧名思義，就是輪流請(qǐng)求，基于上篇文章的介紹，我們將負(fù)載均衡策略聚焦于default.conf文件的upstream。

upstream backend {server web02:80;server web03:80; }

在瀏覽器中對(duì)localhost:8080連續(xù)發(fā)出請(qǐng)求，根據(jù)nginx請(qǐng)求日志可以看出web02與web03訪問(wèn)的次數(shù)是相同的。

web01 | 172.24.0.1 - - [26/Jun/2019:10:03:06 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web02 | 172.24.0.3 - - [26/Jun/2019:10:03:06 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web01 | 172.24.0.1 - - [26/Jun/2019:10:03:07 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web03 | 172.24.0.3 - - [26/Jun/2019:10:03:07 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web02 | 172.24.0.3 - - [26/Jun/2019:10:05:25 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web01 | 172.24.0.1 - - [26/Jun/2019:10:05:25 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web03 | 172.24.0.3 - - [26/Jun/2019:10:05:26 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web01 | 172.24.0.1 - - [26/Jun/2019:10:05:26 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web02 | 172.24.0.3 - - [26/Jun/2019:10:05:27 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web01 | 172.24.0.1 - - [26/Jun/2019:10:05:27 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web01 | 172.24.0.1 - - [26/Jun/2019:10:05:27 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web03 | 172.24.0.3 - - [26/Jun/2019:10:05:27 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-"

加權(quán)輪詢

加權(quán)輪詢是指基于上文中的輪詢，加上一定的權(quán)重，使得某個(gè)服務(wù)器被轉(zhuǎn)發(fā)的次數(shù)更多一些，加權(quán)通過(guò)在IP后方拼接weight實(shí)現(xiàn)。

upstream backend {server web02:80 weight=5;server web03:80 weight=1; }

weight值越大，所分配的請(qǐng)求就越多，根據(jù)nginx的請(qǐng)求日志可以看出web02被訪問(wèn)了8次，web03被訪問(wèn)了兩次。

web01 | 172.24.0.1 - - [26/Jun/2019:14:48:13 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web02 | 172.24.0.3 - - [26/Jun/2019:14:48:13 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web02 | 172.24.0.3 - - [26/Jun/2019:14:48:16 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web01 | 172.24.0.1 - - [26/Jun/2019:14:48:16 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web01 | 172.24.0.1 - - [26/Jun/2019:14:48:16 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web02 | 172.24.0.3 - - [26/Jun/2019:14:48:16 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web01 | 172.24.0.1 - - [26/Jun/2019:14:48:17 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web03 | 172.24.0.3 - - [26/Jun/2019:14:48:17 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web01 | 172.24.0.1 - - [26/Jun/2019:14:48:17 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web02 | 172.24.0.3 - - [26/Jun/2019:14:48:17 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web02 | 172.24.0.3 - - [26/Jun/2019:14:48:18 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web01 | 172.24.0.1 - - [26/Jun/2019:14:48:18 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web01 | 172.24.0.1 - - [26/Jun/2019:14:48:19 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web02 | 172.24.0.3 - - [26/Jun/2019:14:48:19 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web01 | 172.24.0.1 - - [26/Jun/2019:14:48:19 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web02 | 172.24.0.3 - - [26/Jun/2019:14:48:19 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web01 | 172.24.0.1 - - [26/Jun/2019:14:48:20 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web02 | 172.24.0.3 - - [26/Jun/2019:14:48:20 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web03 | 172.24.0.3 - - [26/Jun/2019:14:48:20 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web01 | 172.24.0.1 - - [26/Jun/2019:14:48:20 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-"

ip_hash

如果一個(gè)客戶端的請(qǐng)求可能被轉(zhuǎn)發(fā)到任何一臺(tái)服務(wù)器，可能會(huì)導(dǎo)致每臺(tái)服務(wù)器都緩存了該客戶端的信息，比較浪費(fèi)資源，ip_hash作用就是通過(guò)客戶端IP的前三個(gè)部分計(jì)算出key，以便將同一個(gè)客戶端的請(qǐng)求轉(zhuǎn)發(fā)到指定的服務(wù)器中，配置的方法比較簡(jiǎn)單，只需要在upstream上方加一行代碼即可。

upstream backend {ip_hash;server web02:80;server web03:80; }

重復(fù)請(qǐng)求了5次，通過(guò)日志看出請(qǐng)求一直被鎖定在了web03上。

web01 | 172.24.0.1 - - [27/Jun/2019:11:48:15 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web03 | 172.24.0.2 - - [27/Jun/2019:11:48:15 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "172.24.0.1" web01 | 172.24.0.1 - - [27/Jun/2019:11:48:22 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web03 | 172.24.0.2 - - [27/Jun/2019:11:48:22 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "172.24.0.1" web03 | 172.24.0.2 - - [27/Jun/2019:11:48:23 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "172.24.0.1" web01 | 172.24.0.1 - - [27/Jun/2019:11:48:23 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web03 | 172.24.0.2 - - [27/Jun/2019:11:48:24 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "172.24.0.1" web01 | 172.24.0.1 - - [27/Jun/2019:11:48:24 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web01 | 172.24.0.1 - - [27/Jun/2019:11:48:24 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web03 | 172.24.0.2 - - [27/Jun/2019:11:48:24 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "172.24.0.1"

url_hash

這種模式是將url進(jìn)行哈希，然后定位到具體的某一臺(tái)服務(wù)器，相同的url永遠(yuǎn)會(huì)被轉(zhuǎn)發(fā)到同一臺(tái)服務(wù)器上。

upstream backend {hash $request_uri;server web02:80;server web03:80; }

通過(guò)瀏覽器訪問(wèn)兩次http://localhost:8080，通過(guò)日志可以看到轉(zhuǎn)發(fā)被固定在了web03。

web01 | 172.24.0.1 - - [27/Jun/2019:11:58:31 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web03 | 172.24.0.4 - - [27/Jun/2019:11:58:31 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web03 | 172.24.0.4 - - [27/Jun/2019:11:58:38 +0000] "GET / HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web01 | 172.24.0.1 - - [27/Jun/2019:11:58:38 +0000] "GET / HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-"

在鏈接后面拼接一些參數(shù)，就可以看到轉(zhuǎn)發(fā)發(fā)生了變化，固定在了web02，隨著參數(shù)的變化，請(qǐng)求也會(huì)采用輪詢的方式轉(zhuǎn)發(fā)給服務(wù)器，但使用過(guò)的url再訪問(wèn)就不會(huì)再變化了。

web02 | 172.24.0.4 - - [27/Jun/2019:11:59:54 +0000] "GET /?a=1 HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web01 | 172.24.0.1 - - [27/Jun/2019:11:59:54 +0000] "GET /?a=1 HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web02 | 172.24.0.4 - - [27/Jun/2019:11:59:55 +0000] "GET /?a=1 HTTP/1.0" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-" web01 | 172.24.0.1 - - [27/Jun/2019:11:59:55 +0000] "GET /?a=1 HTTP/1.1" 304 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_14_2) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/74.0.3729.169 Safari/537.36" "-"

轉(zhuǎn)載于:https://www.cnblogs.com/enochzzg/p/11099354.html

總結(jié)

以上是生活随笔為你收集整理的Nginx多种负载均衡策略搭建的全部?jī)?nèi)容，希望文章能夠幫你解決所遇到的問(wèn)題。

如果覺(jué)得生活随笔網(wǎng)站內(nèi)容還不錯(cuò)，歡迎將生活随笔推薦給好友。