Code: 210. DB::NetException: Connection refused (localhost:9000)

1、为啥子报这个错误呢，因为我在Clickhouse中使用了Mysql引擎，创建一个数据表。当我使用drop database删除数据库之后，发现删除不掉，然后ctrl+c了，之后再次进入clickhouse客户端就报下面的错误了。

[root@master ~]# clickhouse-client -m
ClickHouse client version 20.8.3.18.
Connecting to localhost:9000 as user default.
Code: 210. DB::NetException: Connection refused (localhost:9000)

解决方法，我是先将/var/lib/clickhouse/data下面的创建的mysql引擎的数据库目录删除掉，然后再将/var/lib/clickhouse/metadata下面创建的mysql引擎的数据库目录删除掉，然后再次重启Clickhouse服务，最后启动clickhouse客户端，基本就解决了问题了。如果还是不行，重启服务器试试，再重启Clickhouse服务，最后启动clickhouse客户端。

 

2、可以查看Clickhouse的服务启动状态，如下所示：

[root@master ~]# systemctl status clickhouse-server.service
● clickhouse-server.service - LSB: Yandex clickhouse-server daemon
   Loaded: loaded (/etc/rc.d/init.d/clickhouse-server; bad; vendor preset: disabled)
   Active: active (exited) since 二 2021-02-23 20:04:35 CST; 3h 13min ago
     Docs: man:systemd-sysv-generator(8)
  Process: 1132 ExecStart=/etc/rc.d/init.d/clickhouse-server start (code=exited, status=0/SUCCESS)
    Tasks: 0

2月 23 20:04:31 master systemd[1]: Starting LSB: Yandex clickhouse-server daemon...
2月 23 20:04:31 master su[1168]: (to clickhouse) root on none
2月 23 20:04:32 master clickhouse-server[1132]: Start clickhouse-server service: Path to data directory in /etc/clickhouse-server/config.xml: /var...ckhouse/
2月 23 20:04:32 master su[1324]: (to clickhouse) root on none
2月 23 20:04:32 master su[1344]: (to clickhouse) root on none
2月 23 20:04:33 master su[1370]: (to clickhouse) root on none
2月 23 20:04:33 master su[1405]: (to clickhouse) root on none
2月 23 20:04:35 master clickhouse-server[1132]: DONE
2月 23 20:04:35 master systemd[1]: Started LSB: Yandex clickhouse-server daemon.
Hint: Some lines were ellipsized, use -l to show in full.
[root@master ~]# 

 

3、当然了，有的说是修改下面的配置文件，我的不是这个问题，这里简单列一下。

[root@master ~]# vim /etc/clickhouse-server/config.xml

有的说，改成下面这个配置，由于我要远程连接服务器的Clickhouse服务，所以本身就已经改成这个了。