spring-boot-starter-data-redis 远程主机强迫关闭了一个现有连接

Background:

spring-boot-starter-data-redis:2.5.6 连接， 连接池是默认的 lettuce.
redis 版本 6.2.7

console 信息：

org.springframework.data.redis.RedisConnectionFailureException: Unable to connect to Redis; nested exception is org.springframework.data.redis.connection.PoolException: Could not get a resource from the pool; nested exception is io.lettuce.core.RedisConnectionException: Unable to connect to 122.9.12.116:6379
,

at org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory$ExceptionTranslatingConnectionProvider.translateException(LettuceConnectionFactory.java:1671)
at org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory$ExceptionTranslatingConnectionProvider.getConnection(LettuceConnectionFactory.java:1579)
at org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory$SharedConnection.getNativeConnection(LettuceConnectionFactory.java:1365)
at org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory$SharedConnection.getConnection(LettuceConnectionFactory.java:1348)
at org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory.getSharedConnection(LettuceConnectionFactory.java:1089)
at org.springframework.data.redis.connection.lettuce.LettuceConnectionFactory.getConnection(LettuceConnectionFactory.java:421)
at org.springframework.data.redis.core.RedisConnectionUtils.fetchConnection(RedisConnectionUtils.java:193)
at org.springframework.data.redis.core.RedisConnectionUtils.doGetConnection(RedisConnectionUtils.java:144)
at org.springframework.data.redis.core.RedisConnectionUtils.getConnection(RedisConnectionUtils.java:105)
at org.springframework.data.redis.core.RedisTemplate.execute(RedisTemplate.java:209)
at org.springframework.data.redis.core.RedisTemplate.execute(RedisTemplate.java:189)
at org.springframework.data.redis.core.RedisTemplate.hasKey(RedisTemplate.java:768)
at com.erato.redisdemo0914.cost.common.util.CostCacheHelper.getNowPeriod(CostCacheHelper.java:91)
at com.erato.redisdemo0914.cost.common.costCacheHelperTest.testGetNowPeriod(costCacheHelperTest.java:27)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
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Caused by: org.springframework.data.redis.connection.PoolException: Could not get a resource from the pool; nested exception is io.lettuce.core.RedisConnec