问题描述

在Spring Boot项目中使用Jedis客户端连接Redis时，出现如下异常： 

Exception in thread "main" org.springframework.data.redis.RedisConnectionFailureException: Cannot get Jedis connection; nested exception is redis.clients.jedis.exceptions.JedisConnectionException: Could not get a resource from the pool
	at org.springframework.data.redis.connection.jedis.JedisConnectionFactory.fetchJedisConnector(JedisConnectionFactory.java:281)
	at org.springframework.data.redis.connection.jedis.JedisConnectionFactory.getConnection(JedisConnectionFactory.java:475)
	at org.springframework.data.redis.core.RedisConnectionUtils.doGetConnection(RedisConnectionUtils.java:132)
	at org.springframework.data.redis.core.RedisConnectionUtils.getConnection(RedisConnectionUtils.java:95)
	at org.springframework.data.redis.core.RedisConnectionUtils.getConnection(RedisConnectionUtils.java:82)
	at org.springframework.data.redis.core.RedisTemplate.execute(RedisTemplate.java:215)
	at org.springframework.data.redis.core.RedisTemplate.execute(RedisTemplate.java:188)
	at org.springframework.data.redis.core.AbstractOperations.execute(AbstractOperations.java:96)
	at org.springframework.data.redis.core.DefaultValueOperations.set(DefaultValueOperations.java:236)
	at cn.zyt.springbootlearning.config.RedisConfiguration.main(RedisConfiguration.java:59)
Caused by: redis.clients.jedis.exceptions.JedisConnectionException: Could not get a resource from the pool
	at redis.clients.jedis.util.Pool.getResource(Pool.java:59)
	at redis.clients.jedis.JedisPool.getResource(JedisPool.java:234)
	at redis.clients.jedis.JedisPool.getResource(JedisPool.java:15)
	at org.springframework.data.redis.connection.jedis.JedisConnectionFactory.fetchJedisConnector(JedisConnectionFactory.java:271)
	... 9 more
Caused by: redis.clients.jedis.exceptions.JedisDataException: ERR Client sent AUTH, but no password is set
	at redis.clients.jedis.Protocol.processError(Protocol.java:132)
	at redis.clients.jedis.Protocol.process(Protocol.java:166)
	at redis.clients.jedis.Protocol.read(Protocol.java:220)
	at redis.clients.jedis.Connection.readProtocolWithCheckingBroken(Connection.java:318)
	at redis.clients.jedis.Connection.getStatusCodeReply(Connection.java:236)
	at redis.clients.jedis.BinaryJedis.auth(BinaryJedis.java:2229)
	at redis.clients.jedis.JedisFactory.makeObject(JedisFactory.java:119)
	at org.apache.commons.pool2.impl.GenericObjectPool.create(GenericObjectPool.java:889)
	at org.apache.commons.pool2.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:424)
	at org.apache.commons.pool2.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:349)
	at redis.clients.jedis.util.Pool.getResource(Pool.java:50)
	... 12 more

解决方法

该问题的出现是由于Redis中本身没有设置密码，但连接时指定了密码则会带Auth，这就造成了如上的异常。最简单的解决方法：将连接时设置的密码删掉后，重新尝试异常即解决。

此外如果需要使用Redis的签名认证，可以使用如下两种方式设置Redis中密码：

1. 在指定配置文件启动时：

yitian@heron01:/usr/local/bin$ redis-server /etc/redis/redis.conf

在配置文件中进行如下设置，既可以指定Redis的密码（将下面foobared改为你需要设置的密码），此时在Jedis连接Redis时需要指定密码。

2. 使用命令行设置Redis密码，此时并不会改变配置文件中的设置，但也可以使密码的设置生效。设置后，客户端重新连接server则需要密码。

config set requirepass 123456

查看密码设置的情况：

config get requirepass

带密码命令行登录Server： 

redis-cli -p 6379 -a 123456

注意，上述指定redis.conf配置文件启动的方式可以使配置文件中的密码生效，而默认redis-server不带配置文件（或配置文件为默认状态时），是没有设置密码的，所以命令行cli连接无需验证，而Jedis登录也不需要带password。