Article directory
- The role of Nginx
- What you need to know before learning Nginx
- Nginx installation
- Common commands of Nginx
- Nginx configuration file
- Implementation example of reverse proxy one
- Implementation example 2 of reverse proxy
- load balancing
- nginx allocation server strategy
- Dynamic and static separation configuration
- High availability
The role of Nginx
Nginx is a high-performance HTTP and reverse proxy server. It is very powerful in handling high concurrency and can withstand high loads. Reports indicate that it can support up to 50,000 concurrent connections.
What you need to know before learning Nginx
forward proxy
If we access our school's intranet but we can't access it directly, we need a proxy service .
We go through
1.Configure proxy server
2. By accessing the proxy server
3. The proxy server will then access our school's intranet
so that we can access our school's intranet
. The biggest feature of forward proxy is
that a proxy server needs to be configured on the client to access the designated website.
reverse proxy
The reverse proxy is the 9001 port of our access server,
and then the server goes to the 8001 port of tomcat.
For users, we do not know the port of tomcat.
When we use it, the reverse proxy server and tomcat are integrated
reverse proxy features. Yes
What is exposed is the proxy server address, hiding the real server IP address.
load balancing
Increase the number of servers, then distribute the requests to each server, and change the original request to a single server to distribute the request to multiple servers, and distribute the load to different servers, which is what we call load balanced
Suppose there are 900 requests to the nginx server. The nginx server will give 300 requests to each of these three ports and let them work together. The same number
Dynamic and static separation
The common way we learned before is to put such dynamic resources and static resources together. 
In order to reduce the burden of tomcat, nginx separates dynamic resources and static resources
Nginx installation
https://segmentfault.com/a/1190000040125857
Common commands of Nginx
First of all, I have to enter the nginx directory and I installed it here
1. Check the nginx version number
./nginx -v
2. Start nginx
./nginx
3. Stop nginx
./nginx -s stop
4. Reload nginx
./nginx -s reload
Nginx configuration file
[root@localhost ~]# vi /usr/local/nginx/conf/nginx.conf
# 第一部分 全局块:配置服务器整体运行的配置指令
# 处理并发数,越大处理越多
worker_processes 1;
# 第二部分 events块:设置nginx服务器和用户的网络连接
events {
# 支持最大连接数为1024
worker_connections 1024;
}
# 第三部分 http块:代理、缓存、日志等
# http块中还分为2个块:
# http全局块
# http 全局块配置的指令包括文件引入
# server块
# 配置一个主机信息
http {
# 设定mime类型,类型由mime.type文件定义
include mime.types;
default_type application/octet-stream;
sendfile on;
keepalive_timeout 65;
server {
# 端口
listen 80;
# 域名
server_name localhost;
# /目录下
location / {
# html文件
root html;
}
}
Implementation example of reverse proxy one
The effect to be achieved is
Open the browser, enter the address www.123.com in the browser address bar (I use the domain name I purchased and configured myself), and jump to the main page of the liunx system tomcat
Ready to work
Install tomcat in the liunx system, use the default port 8080
* tomcat installation files are placed in the liunx system, decompress
* into the bin directory of tomcat, ./startup.sh starts the tomcat server
Ports that are open to the outside world
firewall-cmd --add-port=8080/tcp --permanent
firewall-cmd --reload to
view the open port numbers
firewall-cmd --list-all
The process of accessing is
The browser accesses nginx through the domain name and then nginx is forwarded to tomcat
nginx request forwarding configuration (reverse proxy)
If there is access to port 80 of this machine, it will be forwarded to 107.0.0.1:8080, which is the home page of tomcat
.
After the modification, restart nginx to take effect
Implementation example 2 of reverse proxy
effect to be achieved
Using the nginx reverse proxy, jump to services with different ports according to the access path. The
nginx listening port is 9001
to access http://192.168.17.129:9001/edu/ and directly jump to 127.0.0.1:8080
to access http:// 192.168.17.129:9001/vod/ jumps directly to 127.0.0.1:8081
Ready to work
(1) Prepare two tomcat servers, one port 8080 and one port 8081
(2) Create folders and test pages
Reference instructions:
# 创建2个文件
mkdir tomcat8080 tomcat8081
# 复制tomcat到2个文件中
cp apache-tomcat-7.0.70.tar.gz tomcat8080
cp apache-tomcat-7.0.70.tar.gz tomcat8081
# 关闭以前的tomcat
apache-tomcat-7.0.70/bin/shutdown.sh
# 进入第一个tomcat
cd tomcat8080
# 解压tomcat
tar -zxvf apache-tomcat-7.0.70.tar.gz
# 添加网页
mkdir /root/tomcat8080/apache-tomcat-7.0.70/webapps/aaa
vi /root/tomcat8080/apache-tomcat-7.0.70/webapps/aaa/aaa.html
this is 8080!!!
# 启动tomcat
apache-tomcat-7.0.70/bin/startup.sh
# 进入第二个tomcat
cd tomcat8081
# 解压文件
tar -zxvf apache-tomcat-7.0.70.tar.gz
# 修改端口
vi apache-tomcat-7.0.70/conf/server.xml
# 22行改为8015
<Server port="8015" shutdown="SHUTDOWN">
# 71行改为8081
<Connector port="8081" protocol="HTTP/1.1"
connectionTimeout="20000"
redirectPort="8443" />
# 退出配置文件
:wq
mkdir /root/tomcat8081/apache-tomcat-7.0.70/webapps/aaa
vi /root/tomcat8081/apache-tomcat-7.0.70/webapps/bbb/aaa.html
this is 8081!!!
# 启动tomcat
apache-tomcat-7.0.70/bin/startup.sh
# 查看端口号
netstat -nultp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 0.0.0.0:80 0.0.0.0:* LISTEN 31853/nginx: master
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 988/sshd
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN 1250/master
tcp6 0 0 127.0.0.1:8015 :::* LISTEN 32369/java
tcp6 0 0 :::8080 :::* LISTEN 32274/java
tcp6 0 0 :::8081 :::* LISTEN 32369/java
tcp6 0 0 :::22 :::* LISTEN 988/sshd
tcp6 0 0 ::1:25 :::* LISTEN 1250/master
tcp6 0 0 127.0.0.1:8005 :::* LISTEN 32274/java
tcp6 0 0 :::8009 :::* LISTEN 32274/java
udp 0 0 127.0.0.1:323 0.0.0.0:* 673/chronyd
udp6 0 0 ::1:323 :::* 673/chronyd
# nginx的配置文件设置
# 在http中添加一个server
server {
# 监听9001
listen 9001;
server_name localhost;
# 链接中有aaa就跳转8080
location ~ /edu/ {
proxy_pass http://127.0.0.1:8080;
}
# 链接中含有bbb跳转8081
location ~ /vod/ {
proxy_pass http://127.0.0.1:8081;
}
}
#####################################################
1、= ：用于不含正则表达式的 uri 前，要求请求字符串与 uri 严格匹配，如果匹配成功，就停止继续向下搜索并立即处理该请求。
2、~：用于表示 uri 包含正则表达式，并且区分大小写。
3、~*：用于表示 uri 包含正则表达式，并且不区分大小写。
4、^~：用于不含正则表达式的 uri 前，要求 Nginx 服务器找到标识 uri 和请求字符串匹配度最高的 location 后，立即使用此 location 处理请求，而不再使用 location块中的正则 uri 和请求字符串做匹配。
注意：如果 uri 包含正则表达式，则必须要有 ~ 或者 ~* 标识。
#####################################################
# 重新加载nginx
/usr/local/nginx/sbin/nginx -s reload
load balancing
achieve effect
(1) Enter the address http://192.168.17.129/edu/a.html in the browser address bar, the load balancing effect, the average port 8080 and 8081
Ready to work
(1) Prepare two tomcat servers, one 8080 and one 8081
(2) In the webapps directory of the two tomcats, create a folder named edu, and create a page a.html in the edu folder for testing
Load balancing configuration in nginx configuration file
This means that if I access my host address and it starts with /, then I will forward it to the two addresses configured in myserver.
Refer to the instructions
# 创建2个文件
mkdir tomcat8080 tomcat8081
# 复制tomcat到2个文件中
cp apache-tomcat-7.0.70.tar.gz tomcat8080
cp apache-tomcat-7.0.70.tar.gz tomcat8081
# 关闭以前的tomcat
apache-tomcat-7.0.70/bin/shutdown.sh
# 进入第一个tomcat
cd tomcat8080
# 解压tomcat
tar -zxvf apache-tomcat-7.0.70.tar.gz
# 添加网页
mkdir /root/tomcat8080/apache-tomcat-7.0.70/webapps/aaa
vi /root/tomcat8080/apache-tomcat-7.0.70/webapps/aaa/aaa.html
this is 8080!!!
# 启动tomcat
apache-tomcat-7.0.70/bin/startup.sh
# 进入第二个tomcat
cd tomcat8081
# 解压文件
tar -zxvf apache-tomcat-7.0.70.tar.gz
# 修改端口
vi apache-tomcat-7.0.70/conf/server.xml
# 22行改为8015
<Server port="8015" shutdown="SHUTDOWN">
# 71行改为8081
<Connector port="8081" protocol="HTTP/1.1"
connectionTimeout="20000"
redirectPort="8443" />
# 退出配置文件
:wq
mkdir /root/tomcat8081/apache-tomcat-7.0.70/webapps/aaa
vi /root/tomcat8081/apache-tomcat-7.0.70/webapps/bbb/aaa.html
this is 8081!!!
# 启动tomcat
apache-tomcat-7.0.70/bin/startup.sh
# 查看端口号
netstat -nultp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 0.0.0.0:80 0.0.0.0:* LISTEN 31853/nginx: master
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 988/sshd
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN 1250/master
tcp6 0 0 127.0.0.1:8015 :::* LISTEN 32369/java
tcp6 0 0 :::8080 :::* LISTEN 32274/java
tcp6 0 0 :::8081 :::* LISTEN 32369/java
tcp6 0 0 :::22 :::* LISTEN 988/sshd
tcp6 0 0 ::1:25 :::* LISTEN 1250/master
tcp6 0 0 127.0.0.1:8005 :::* LISTEN 32274/java
tcp6 0 0 :::8009 :::* LISTEN 32274/java
udp 0 0 127.0.0.1:323 0.0.0.0:* 673/chronyd
udp6 0 0 ::1:323 :::* 673/chronyd
# nginx配置文件设置
vi /usr/local/nginx/conf/nginx.conf
http {
include mime.types;
default_type application/octet-stream;
sendfile on;
keepalive_timeout 65;
##################################
upstream myserver{
server 192.168.2.177:8080;
server 192.168.2.177:8081;
}
##################################
server {
listen 80;
server_name localhost;
location / {
root html;
##################################
proxy_pass http://myserver;
##################################
index index.html index.htm;
}
error_page 500 502 503 504 /50x.html;
location = /50x.html {
root html;
}
}
}
:wq
# 重新加载服务器
./nginx -s reload
nginx allocation server strategy
First polling (default)
Each request is allocated to different back-end servers one by one in chronological order. If the back-end server goes down, it can be automatically eliminated.
The second weight
weight means the weight defaults to 1, the higher the weight, the more clients will be assigned
server 192.168.2.177:8080 weight=5
server 192.168.2.177:8081 weight=10
The third ip_hash
Each request is allocated according to the hash result of the access ip, so that each visitor has a fixed access to a backend server
upstream server_pool{
ip_hash;
server 192.168.5.21:8080;
server 192.168.5.22:8081;
}
The fourth kind of fair (third party)
Requests are allocated according to the response time of the back-end server, and those with short response times are given priority.
upstream server_pool{
server 192.168.5.21:80;
server 192.168.5.22:80;
fair;
}
Dynamic and static separation configuration
What is static and dynamic separation?
Different request forwarding can be achieved by specifying different suffix names by location. By setting the expires parameter, you can make the browser cache expire time and reduce the request and traffic before the server. The specific definition of Expires: It is to set an expiration time for a resource, that is to say, it does not need to go to the server for verification, and it can directly confirm whether it expires through the browser itself, so no additional traffic will be generated. This approach is ideal for resources that change infrequently. (If the file is updated frequently, it is not recommended to use Expires to cache), I set 3d here, which means that the URL is accessed within these 3 days, a request is sent, and the last update time of the file on the server has not changed. The server fetches and returns the status code 304. If there is any modification, it is directly downloaded from the server and the status code 200 is returned.
Simply put, dynamic resources are placed in tomcat and static resources are put together separately to reduce the workload of tomcat
Ready to work
Prepare static resources in the liunx system for access
configure nginx.cof
The effect achieved by autoindex on is like this
High availability
What is high availability
High availability means that after a master server is sent, the slave server can work for the master server
The implementation is that the two servers display the same virtual ip address to the outside world, and then the user generally accesses the main server and the main server sends it to the backup. Even if the main server sends the user, the user will not feel it.
Reference instructions
# 主服务器
vi /etc/keepalived/keepalived.conf
gbal_defs {
notification_email {
[email protected]
[email protected]
[email protected]
}
notification_email_from [email protected]
smtp_server 192.168.2.177
smtp_connect_timeout 30
# 本机主机名,改不改无所谓
router_id LVS_DEVEL
}
vrrp_script chk_http_port {
# 检测脚本的位置
script "/usr/local/src/nginx_check.sh"
# 检测脚本执行的间隔
interval 2
# 执行完本高可用权重怎么的改变
weight 2
}
vrrp_instance VI_1 {
# 主服务器 MASTER 备份服务器 BACKUP
state MASTER
# 网卡名
interface ens33
# 主、备机的virtual_router_id 必须相同
virtual_router_id 51
# 主、备机取不同的优先级，主机值较大，备份机值较小
priority 100
# 一秒检测一次心跳
advert_int 1
# 验证方式为密码 密码1111
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
# 虚拟ip为192.168.2.50
192.168.2.50
}
}
:wq
# 备份服务器
vi /etc/keepalived/keepalived.conf
gbal_defs {
notification_email {
[email protected]
[email protected]
[email protected]
}
notification_email_from [email protected]
smtp_server 192.168.2.177
smtp_connect_timeout 30
# 本机主机名,改不改无所谓
router_id LVS_DEVEL
}
vrrp_script chk_http_port {
# 检测脚本的位置
script "/usr/local/src/nginx_check.sh"
# 检测脚本执行的间隔
interval 2
# 执行完本高可用权重怎么的改变
weight 2
}
vrrp_instance VI_1 {
# 主服务器 MASTER 备份服务器 BACKUP
state BACKUP
# 网卡名
interface ens33
# 主、备机的virtual_router_id 必须相同
virtual_router_id 51
# 主、备机取不同的优先级，主机值较大，备份机值较小
priority 90
# 一秒检测一次心跳
advert_int 1
# 验证方式为密码 密码1111
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
# 虚拟ip为192.168.2.50
192.168.2.50
}
}
:wq
# 编写脚本文件放入2台服务器的/usr/local/src下
vi /usr/local/src/nginx_check.sh
#!/bin/bash
A=`ps -C nginx –no-header |wc -l`
if [ $A -eq 0 ];then
/usr/local/nginx/sbin/nginx
sleep 2
if [ `ps -C nginx --no-header |wc -l` -eq 0 ];then
killall keepalived
fi
fi
:wq
# 2台服务器启动nginx和keepalived
systemctl restart keepalived
/usr/local/nginx/sbin/nginx
stop master server
systemctl stop keepalived
[root@localhost ~]# netstat -nultp
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN 1003/sshd
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN 1220/master
tcp6 0 0 :::22 :::* LISTEN 1003/sshd
tcp6 0 0 ::1:25 :::* LISTEN 1220/master
udp 0 0 127.0.0.1:323 0.0.0.0:* 661/chronyd
udp6 0 0 ::1:323 :::* 661/chronyd
then visit again