通过Jedis客户端连接不到redis（二）

骑猪看日落 2022-07-16 12:16 221阅读 0赞

之前我的一篇文章，也是解决Jedis连接不到redis的，但是情况不一样，之前的问题主要是防火墙的问题，但是现在看来并不是防火墙的问题，因为redis自身也有配置来限制外网的访问，所以当时也不知道为什么就可以了，今天主要以redis配置的角度来看一下，如何解决外网访问redis的问题。

首先还是描述一下问题：

public static void main(String[] args) {
    		Jedis jedis = new Jedis("192.168.1.118", 6380);
    		System.out.println(jedis);
    		jedis.ping();
    	}

上面是测试代码，下面是报错信息：

Exception in thread "main" redis.clients.jedis.exceptions.JedisConnectionException: java.net.ConnectException: Connection refused: connect
    	at redis.clients.jedis.Connection.connect(Connection.java:207)
    	at redis.clients.jedis.BinaryClient.connect(BinaryClient.java:93)
    	at redis.clients.jedis.Connection.sendCommand(Connection.java:126)
    	at redis.clients.jedis.Connection.sendCommand(Connection.java:121)
    	at redis.clients.jedis.BinaryClient.ping(BinaryClient.java:106)
    	at redis.clients.jedis.BinaryJedis.ping(BinaryJedis.java:195)
    	at com.atguigu.redis.test.TestPing.main(TestPing.java:10)
    Caused by: java.net.ConnectException: Connection refused: connect
    	at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method)
    	at java.net.DualStackPlainSocketImpl.socketConnect(Unknown Source)
    	at java.net.AbstractPlainSocketImpl.doConnect(Unknown Source)
    	at java.net.AbstractPlainSocketImpl.connectToAddress(Unknown Source)
    	at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
    	at java.net.PlainSocketImpl.connect(Unknown Source)
    	at java.net.SocksSocketImpl.connect(Unknown Source)
    	at java.net.Socket.connect(Unknown Source)
    	at redis.clients.jedis.Connection.connect(Connection.java:184)
    	... 6 more

首先，通过查看linux的防火墙，看看是否是防火墙搞的鬼：

[root@localhost ~]# systemctl status firewalld
    ● firewalld.service - firewalld - dynamic firewall daemon
       Loaded: loaded (/usr/lib/systemd/system/firewalld.service; disabled; vendor preset: enabled)
       Active: inactive (dead)

结果是这样的，inactive是不活动的意思，和active相反，这个比较好理解。

然后使用windows的telnet来试一下，上一篇关于远程连接redis的文章中没有关于telnet的信息，这次不上，

C:\Users\Administrator>telnet 192.168.1.118 6379

结果当然也是连不上了，然后就只能请教万能的百度大哥了：

原来是redis默认只能localhost登录，所以需要开启远程登录。解决方法如下：
    
    　　在redis的配置文件redis.conf中，找到bind localhost注释掉。
    
    　　　　注释掉本机,局域网内的所有计算机都能访问。
    
    　　　　band localhost   只能本机访问,局域网内计算机不能访问。
    
    　　　　bind  局域网IP    只能局域网内IP的机器访问, 本地localhost都无法访问。

上面是从别的地方找到的内容，虽然不是很具体，但是指明了方向，那就是redis.conf，所以

################################## NETWORK #####################################
    
    # By default, if no "bind" configuration directive is specified, Redis listens
    # for connections from all the network interfaces available on the server.
    # It is possible to listen to just one or multiple selected interfaces using
    # the "bind" configuration directive, followed by one or more IP addresses.
    #
    # Examples:
    #
    # bind 192.168.1.100 10.0.0.1
    # bind 127.0.0.1 ::1
    #
    # ~~~ WARNING ~~~ If the computer running Redis is directly exposed to the
    # internet, binding to all the interfaces is dangerous and will expose the
    # instance to everybody on the internet. So by default we uncomment the
    # following bind directive, that will force Redis to listen only into
    # the IPv4 lookback interface address (this means Redis will be able to
    # accept connections only from clients running into the same computer it
    # is running).
    #
    # IF YOU ARE SURE YOU WANT YOUR INSTANCE TO LISTEN TO ALL THE INTERFACES
    # JUST COMMENT THE FOLLOWING LINE.
    # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    bind 127.0.0.1
    bind 192.168.1.118
    
    # Protected mode is a layer of security protection, in order to avoid that
    # Redis instances left open on the internet are accessed and exploited.
    #
    # When protected mode is on and if:
    #

上面是redis.conf中的内容

bind 192.168.1.118

是我后来添加的，也就是加了这句话之后，才可以正常的访问了。

public static void main(String[] args) {
    		Jedis jedis = new Jedis("192.168.1.118", 6379);
    		System.out.println(jedis);
    		String ping = jedis.ping();
    		System.out.println(ping);
    	}

redis.clients.jedis.Jedis@6ff3c5b5
    PONG