nginx+Tomcat 负载均衡

Posted 2022-04-20 睡着的冰淇淋

实验环境

实验目的

当请求访问到我这台 nginx 服务器时我本身不做为 web 服务器解析，我把你的请求转换到后台的服务器做解析，让你们做解析。

实验准备

实现三台设备的局域网互通

三台虚拟机之间使用 VMnet3 对接，只需要配置IP地址，不需要配置网关

nginx

[root@bobi ~]# vim /etc/sysconfig/network-scripts/ifcfg-ens33 
[root@bobi ~]# cat /etc/sysconfig/network-scripts/ifcfg-ens33 
TYPE=Ethernet
BOOTPROTO=static
DEVICE=ens33
ONBOOT=yse
IPADDR=172.16.1.1
NETMASK=255.255.255.0
[root@bobi ~]# 
[root@bobi ~]# ifdown ens33
^[[ADevice ens33 successfully disconnected.
[root@bobi ~]# ifdown ens33
[root@bobi ~]# ifup ens33
Connection successfully activated (D-Bus active path: /org/freedesktop/NetworkManager/ActiveConnection/7)
[root@bobi ~]# 
[root@bobi ~]# ipaddr
bash: ipaddr: command not found...
[root@bobi ~]# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:f4:e9:60 brd ff:ff:ff:ff:ff:ff
    inet 172.16.1.1/24 brd 172.16.1.255 scope global noprefixroute ens33
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fef4:e960/64 scope link 
       valid_lft forever preferred_lft forever
3: virbr0: <BROADCAST,MULTICAST> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
    link/ether 52:54:00:bd:8a:7a brd ff:ff:ff:ff:ff:ff
4: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast master virbr0 state DOWN group default qlen 1000
    link/ether 52:54:00:bd:8a:7a brd ff:ff:ff:ff:ff:ff
5: ens37: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:f4:e9:6a brd ff:ff:ff:ff:ff:ff
    inet 192.168.192.144/24 brd 192.168.192.255 scope global noprefixroute dynamic ens37
       valid_lft 1268sec preferred_lft 1268sec
    inet6 fe80::b056:e73b:2369:6dce/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
[root@bobi ~]#

tomcat1

[root@bobi ~]# vim /etc/sysconfig/network-scripts/ifcfg-eth0 
[root@bobi ~]# cat /etc/sysconfig/network-scripts/ifcfg-eth0 
TYPE=Ethernet
BOOTPROTO=static
DEVICE=eth0
ONBOOT=yes
IPADDR=172.16.1.10
NETMASK=255.255.255.0
[root@bobi ~]# 
[root@bobi ~]# ifdown eth0
Device eth0 successfully disconnected.
[root@bobi ~]# ifup eth0
Connection successfully activated (D-Bus active path: /org/freedesktop/NetworkManager/ActiveConnection/7)
[root@bobi ~]# 
[root@bobi ~]# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:57:b3:2f brd ff:ff:ff:ff:ff:ff
    inet 172.16.1.10/24 brd 172.16.1.255 scope global noprefixroute eth0
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe57:b32f/64 scope link 
       valid_lft forever preferred_lft forever
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:57:b3:39 brd ff:ff:ff:ff:ff:ff
    inet 192.168.192.146/24 brd 192.168.192.255 scope global noprefixroute dynamic eth1
       valid_lft 1638sec preferred_lft 1638sec
    inet6 fe80::f43e:7f0c:bfff:d907/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
[root@bobi ~]#

tomcat2

[root@bobi ~]# vim /etc/sysconfig/network-scripts/ifcfg-eth0 
[root@bobi ~]# cat /etc/sysconfig/network-scripts/ifcfg-eth0 
TYPE=Ethernet
BOOTPROTO=static
DEVICE=eth0
ONBOOT=yes
IPADDR=172.16.1.20
NETMASK=255.255.255.0
[root@bobi ~]# 
[root@bobi ~]# ifdown eth0
Device eth0 successfully disconnected.
[root@bobi ~]# ifup eth0
Connection successfully activated (D-Bus active path: /org/freedesktop/NetworkManager/ActiveConnection/5)
[root@bobi ~]# 
[root@bobi ~]# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:02:69:75 brd ff:ff:ff:ff:ff:ff
    inet 172.16.1.20/24 brd 172.16.1.255 scope global noprefixroute eth0
       valid_lft forever preferred_lft forever
    inet6 fe80::20c:29ff:fe02:6975/64 scope link 
       valid_lft forever preferred_lft forever
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:02:69:7f brd ff:ff:ff:ff:ff:ff
    inet 192.168.192.145/24 brd 192.168.192.255 scope global noprefixroute dynamic eth1
       valid_lft 1155sec preferred_lft 1155sec
    inet6 fe80::f59b:e22f:f08a:8728/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever
[root@bobi ~]#

测试

nginx 和 tomcat

tomcat 之间

网络互通

开启 Nginx 服务

修改 tomcat1 和 tomcat2 的主页内容

<用于区分两个 tomcat 服务>

tomcat1

[root@bobi webapps]# ls
docs  examples  host-manager  manager  ROOT
[root@bobi webapps]# mv ROOT/ ROOTBAK
[root@bobi webapps]# ls
docs  examples  host-manager  manager  ROOTBAK
[root@bobi webapps]# 
[root@bobi webapps]# mkdir ROOT
[root@bobi webapps]# cd ROOT
[root@bobi ROOT]# ls
[root@bobi ROOT]# vim index.jsp
[root@bobi ROOT]# 
[root@bobi ROOT]# cat index.jsp 
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<html>
<head>
<title>JSP TEST1 page</title>
</head>
<body> 
<% out.println("Welcome to TEST1 web,http:/www.test1.com");%>
</body>
</html>

tomcat2

[root@bobi webapps]# ls
docs  examples  host-manager  manager  ROOT
[root@bobi webapps]# mv ROOT/ ROOTBAK
[root@bobi webapps]# ls
docs  examples  host-manager  manager  ROOTBAK
[root@bobi webapps]# 
[root@bobi webapps]# mkdir ROOT
[root@bobi webapps]# cd ROOT
[root@bobi ROOT]# ls
[root@bobi ROOT]# vim index.jsp
[root@bobi ROOT]# 
[root@bobi ROOT]# cat index.jsp 
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<html>
<head>
<title>JSP TEST2 page</title>
</head>
<body> 
<% out.println("Welcome to TEST2 web,http:/www.test2.com");%>
</body>
</html>

配置 Nginx 服务端

安装 Nginx 反向代理服务

./configure --prefix=/usr/local/nginx --user=nginx --group=nginx --with-file-aio --with-http_stub_status_module --with-http_gzip_static_module --with-http_flv_module --with-http_ssl_module

[root@bobi src]# cd nginx-1.6.2/
[root@bobi nginx-1.6.2]# ./configure --prefix=/usr/local/nginx --user=nginx --group=nginx --with-file-aio --with-http_stub_status_module --with-http_gzip_static_module --with-http_flv_module --with-http_ssl_module
checking for OS
 + Linux 3.10.0-1160.el7.x86_64 x86_64
checking for C compiler ... found
 + using GNU C compiler
 + gcc version: 4.8.5 20150623 (Red Hat 4.8.5-44) (GCC) 
...
checking for OpenSSL library ... not found

./configure: error: SSL modules require the OpenSSL library.
You can either do not enable the modules, or install the OpenSSL library
into the system, or build the OpenSSL library statically from the source
with nginx by using --with-openssl=<path> option.

缺少开发组件,安装即可

[root@bobi nginx-1.6.2]# yum install openssl openssl-devel
Loaded plugins: fastestmirror, langpacks
Loading mirror speeds from cached hostfile
dvdrom                                                     | 3.6 kB  00:00:00     
(1/2): dvdrom/group_gz                                     | 153 kB  00:00:00     
(2/2): dvdrom/primary_db                                   | 3.3 MB  00:00:00     
Package 1:openssl-1.0.2k-19.el7.x86_64 already installed and latest version
Resolving Dependencies
...
----------------------------------------------------------------------------------
Total                                                9.1 MB/s | 2.1 MB  00:00     
Dependency Installed:
  keyutils-libs-devel.x86_64 0:1.5.8-3.el7  krb5-devel.x86_64 0:1.15.1-50.el7    
  libcom_err-devel.x86_64 0:1.42.9-19.el7   libselinux-devel.x86_64 0:2.5-15.el7 
  libsepol-devel.x86_64 0:2.5-10.el7        libverto-devel.x86_64 0:0.2.5-4.el7  

Complete!

注：

刚开始 yum install openssl openssl-devel 的时候出现下面的错误

Error downloading packages:
  libsepol-devel-2.5-10.el7.x86_64: [Errno 256] No more mirrors to try.
  libverto-devel-0.2.5-4.el7.x86_64: [Errno 256] No more mirrors to try.
  libselinux-devel-2.5-15.el7.x86_64: [Errno 256] No more mirrors to try.
  keyutils-libs-devel-1.5.8-3.el7.x86_64: [Errno 256] No more mirrors to try.
  krb5-devel-1.15.1-50.el7.x86_64: [Errno 256] No more mirrors to try.
  1:openssl-devel-1.0.2k-19.el7.x86_64: [Errno 256] No more mirrors to try.
  libcom_err-devel-1.42.9-19.el7.x86_64: [Errno 256] No more mirrors to try.

百度一下，需要进行下面的操作

yum clean all
yum makecache
yum update

但是又出现错误

failure: repodata/repomd.xml from dvdrom: [Errno 256] No more mirrors to try.
file:/media/repodata/repomd.xml: [Errno 14] curl#37 - "Couldnt open file /media/repodata/repomd.xml"

最后发现是本地的镜像没有挂载

（虽然在前面的实验中挂载了，但是是临时挂载，重启后就失效了，开机的时候反而忘记了这回事，重新挂载一下就好了）

[root@bobi yum.repos.d]# cd /media/
[root@bobi media]# ls
[root@bobi media]#
[root@bobi media]# mount /dev/cdrom /media/
mount: /dev/sr0 is write-protected, mounting read-only

开发组件安装完成后，继续检查编译环境

[root@bobi nginx-1.6.2]# ./configure --prefix=/usr/local/nginx --user=nginx --group=nginx --with-file-aio --with-http_stub_status_module --with-http_gzip_static_module --with-http_flv_module --with-http_ssl_module
checking for OS
 + Linux 3.10.0-1160.el7.x86_64 x86_64
checking for C compiler ... found
 + using GNU C compiler
 + gcc version: 4.8.5 20150623 (Red Hat 4.8.5-44) (GCC)
 ...
  nginx path prefix: "/usr/local/nginx"
  nginx binary file: "/usr/local/nginx/sbin/nginx"
  nginx configuration prefix: "/usr/local/nginx/conf"
  nginx configuration file: "/usr/local/nginx/conf/nginx.conf"
  nginx pid file: "/usr/local/nginx/logs/nginx.pid"
  nginx error log file: "/usr/local/nginx/logs/error.log"
  nginx http access log file: "/usr/local/nginx/logs/access.log"
  nginx http client request body temporary files: "client_body_temp"
  nginx http proxy temporary files: "proxy_temp"
  nginx http fastcgi temporary files: "fastcgi_temp"
  nginx http uwsgi temporary files: "uwsgi_temp"
  nginx http scgi temporary files: "scgi_temp"

make -j 4

make install

验证

[root@bobi local]# cd /usr/local/nginx/
[root@bobi nginx]# ls
client_body_temp  fastcgi_temp  logs        sbin       uwsgi_temp
conf              html          proxy_temp  scgi_temp
[root@bobi nginx]# cd sbin/
[root@bobi sbin]# ls
nginx  nginx.old

注：

nginx.old 是之前安装的nginx服务

nginx 是现在安装的nginx反向代理服务

配置 Nginx 反向代理服务

修改配置文件

vim /usr/local/nginx/conf/nginx.conf

upstream tomcatserver 
server 172.16.1.10:8080 weight=1;
server 172.16.1.20:8080 weight=1;