CassandraのCqlishコマンドが使えない

#前提・実現したいこと
Apatch　Cassandraのcqlishコマンドを実行しようとすると以下のエラーが出てしまいます。
どなたかお知恵をお貸しいただけたらと思います

#発生しているエラー
[root@SX ~]# /etc/init.d/cassandra start
Starting cassandra (via systemctl): [ OK ]

[root@SX ~]# cqlsh
Connection error: Could not connect to localhost:9160

#実行したコマンド
以下のサイトを参考にCassandraのインストールを行いました。

https://www.liquidweb.com/kb/how-to-install-cassandra-on-centos-7/

＃yum -y update
＃yum -y install java
＃vim /etc/yum.repos.d/datastax.repo

＊＊＊＊＊＊＊下の内容を追記＊＊＊＊＊＊＊＊
[datastax]
name = DataStax Repo for Apache Cassandra
baseurl = http://rpm.datastax.com/community
enabled = 1
gpgcheck = 0
＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊＊

＃yum -y install dsc20
＃/etc/init.d/cassandra start
＃cqlsh
エラーが発生

#Debug.logの内容
DEBUG [main] 2018-04-04 19:38:30,843 DatabaseDescriptor.java:358 - Syncing log with a period of 10000
INFO [main] 2018-04-04 19:38:30,843 DatabaseDescriptor.java:366 - DiskAccessMode 'auto' determined to be mmap, indexAccessMode is mmap
INFO [main] 2018-04-04 19:38:30,845 DatabaseDescriptor.java:420 - Global memtable on-heap threshold is enabled at 227MB
INFO [main] 2018-04-04 19:38:30,845 DatabaseDescriptor.java:424 - Global memtable off-heap threshold is enabled at 227MB
WARN [main] 2018-04-04 19:38:31,640 DatabaseDescriptor.java:466 - Small commitlog volume detected at /usr/local/cassandra/bin/../data/commitlog; setting com
mitlog_total_space_in_mb to 2192. You can override this in cassandra.yaml
WARN [main] 2018-04-04 19:38:31,643 DatabaseDescriptor.java:493 - Small cdc volume detected at /usr/local/cassandra/bin/../data/cdc_raw; setting cdc_total_s
pace_in_mb to 1096. You can override this in cassandra.yaml
WARN [main] 2018-04-04 19:38:34,850 DatabaseDescriptor.java:540 - Only 3.556GiB free across all data volumes. Consider adding more capacity to your cluster
or removing obsolete snapshots
INFO [main] 2018-04-04 19:38:36,293 RateBasedBackPressure.java:123 - Initialized back-pressure with high ratio: 0.9, factor: 5, flow: FAST, window size: 200
0.
INFO [main] 2018-04-04 19:38:36,295 DatabaseDescriptor.java:710 - Back-pressure is disabled with strategy org.apache.cassandra.net.RateBasedBackPressure{hig
h_ratio=0.9, factor=5, flow=FAST}.
DEBUG [main] 2018-04-04 19:38:40,317 YamlConfigurationLoader.java:108 - Loading settings from file:/usr/local/apache-cassandra-3.10/conf/cassandra.yaml
ERROR [main] 2018-04-04 19:38:47,175 CassandraDaemon.java:752 - Exception encountered during startup
java.lang.AbstractMethodError: org.apache.cassandra.utils.JMXServerUtils$Exporter.exportObject(Ljava/rmi/Remote;ILjava/rmi/server/RMIClientSocketFactory;Ljava/rmi/server/RMIServerSocketFactory;Lsun/misc/ObjectInputFilter;)Ljava/rmi/Remote;
at javax.management.remote.rmi.RMIJRMPServerImpl.export(RMIJRMPServerImpl.java:150) ~[na:1.8.0_161]
at javax.management.remote.rmi.RMIJRMPServerImpl.export(RMIJRMPServerImpl.java:135) ~[na:1.8.0_161]
at javax.management.remote.rmi.RMIConnectorServer.start(RMIConnectorServer.java:405) ~[na:1.8.0_161]
at org.apache.cassandra.utils.JMXServerUtils.createJMXServer(JMXServerUtils.java:104) ~[apache-cassandra-3.10.jar:3.10]
at org.apache.cassandra.service.CassandraDaemon.maybeInitJmx(CassandraDaemon.java:144) [apache-cassandra-3.10.jar:3.10]
at org.apache.cassandra.service.CassandraDaemon.setup(CassandraDaemon.java:189) [apache-cassandra-3.10.jar:3.10]
at org.apache.cassandra.service.CassandraDaemon.activate(CassandraDaemon.java:601) [apache-cassandra-3.10.jar:3.10]
at org.apache.cassandra.service.CassandraDaemon.main(CassandraDaemon.java:735) [apache-cassandra-3.10.jar:3.10]