Nginx双机热备的实现步骤

const PATH = ‘/backend/';
//保存到Session
function saveSession() {
    const personName = $('#personName').val();
    if (personName.length <= 0) {
        alert('请输入再保存');
        return;
    }
    $.ajax({
        type:'post',
        url: PATH+"test/save",
        async:false,
        xhrFields: {
            withCredentials: true
        },
        crossDomain: true,
        data: {
            personName:personName
        },
        success: function(json) {
            $('#screen').text(json);
        }
    });
}

//查询Session
function requestServer() {
    $.ajax({
        type:'post',
        url: PATH+"test/query",
        async:false,
        xhrFields: {
            withCredentials: true
        },
        crossDomain: true,
        success: function(json) {
            $('#screen').text(json);
        }
    });
}

@RestController
@RequestMapping("/test")
public class TestController {
	private static final String SERVER = "PC01";

	@Autowired
	private RedisUtil redisUtil;

	@RequestMapping("/save")
	public Object save(String personName, HttpServletRequest request, HttpServletResponse response) {
		String sessionId = request.getRequestedSessionId();
		if (redisUtil.set(sessionId, personName)) {
			return SERVER+",Session保存成功";
		}
		return "Session保存失败";
	}

	@RequestMapping("/query")
	public Object query(HttpServletRequest request) {
		String sessionId = request.getRequestedSessionId();
		Object personName = redisUtil.get(sessionId);
		if (personName != null) {
			return "Hello，" + personName+"，我是"+SERVER;
		}
		return "Session为空";
	}
}

#主备模式，backup只有在主节点故障时才提供服务
upstream backend {  
   server 127.0.0.1:8081;  
   server 127.0.0.1:8082 backup;  
}
server {
    listen       81;
    server_name  localhost;
     location /{
		#前端
        root www/back; 
     } 
     location /backend{
        #反向代理到8081、8082
        proxy_pass http://backend;
     } 
}

[root@localhost test]# lsof -i:8081
COMMAND PID USER FD TYPE DEVICE SIZE/OFF NODE NAME
java 71972 root 13u IPv6 88606 0t0 TCP *:tproxy (LISTEN)
[root@localhost test]# kill -9 71972