Cloud Memorystoreに繋がらない

Question

GCE上にSpringアプリケーションを作成しています。

アプリケーションのSession管理にRedisを使いたくてGCPのCloud Memorystoreと連携しようと思ったのですが、
下記のようなエラーが出てしまい先に進めなくなってしまいました。。。
どなたかご教授お願いします。

（GCEインスタンスとCloud Memorystoreインスタンスは同一ネットワーク、同一リージョンで作成しています。）

Caused by: 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:198)
        at org.springframework.data.redis.connection.jedis.JedisConnectionFactory.getConnection(JedisConnectionFactory.java:345)
        at org.springframework.session.data.redis.config.annotation.web.http.RedisHttpSessionConfiguration$EnableRedisKeyspaceNotificationsInitializer.afterPropertiesSet(RedisHttpSessionConfiguration.java:223)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1637)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1574)
        ... 29 common frames omitted
Caused by: redis.clients.jedis.exceptions.JedisConnectionException: Could not get a resource from the pool
        at redis.clients.util.Pool.getResource(Pool.java:53)
        at redis.clients.jedis.JedisPool.getResource(JedisPool.java:99)
        at redis.clients.jedis.JedisPool.getResource(JedisPool.java:12)
        at org.springframework.data.redis.connection.jedis.JedisConnectionFactory.fetchJedisConnector(JedisConnectionFactory.java:191)
        ... 33 common frames omitted
Caused by: redis.clients.jedis.exceptions.JedisConnectionException: java.net.UnknownHostException: Cloud memorystoreのIPアドレス
        at redis.clients.jedis.Connection.connect(Connection.java:164)
        at redis.clients.jedis.BinaryClient.connect(BinaryClient.java:80)
        at redis.clients.jedis.BinaryJedis.connect(BinaryJedis.java:1677)
        at redis.clients.jedis.JedisFactory.makeObject(JedisFactory.java:87)
        at org.apache.commons.pool2.impl.GenericObjectPool.create(GenericObjectPool.java:868)
        at org.apache.commons.pool2.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:435)
        at org.apache.commons.pool2.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:363)
        at redis.clients.util.Pool.getResource(Pool.java:49)
        ... 36 common frames omitted
Caused by: java.net.UnknownHostException: Cloud memorystoreのIPアドレス
        at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:184)
        at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
        at java.net.Socket.connect(Socket.java:589)
        at redis.clients.jedis.Connection.connect(Connection.java:158)
        ... 43 common frames omitted