Deploy a single-replica OceanBase cluster using the CLI

OceanBase Database can be deployed with a single replica. A single-replica OceanBase cluster can also be scaled out (by adding nodes), so it is also referred to as a standalone cluster.

This topic will guide you through the process of deploying a single-replica OceanBase cluster using the CLI.

Prerequisites

Before installing OceanBase Database, make sure that the following conditions are met:

• The OBServer node has been configured. For more information, see Configure servers and Initialize the OBServer node using oat-cli.

• You have obtained the RPM package of OceanBase Database. For more information, see Prepare installation packages.

Procedure

Step 1: Install the RPM package

1. Install the OceanBase Database RPM package.

   In this step, $rpm_dir indicates the directory where the RPM package is stored, and $rpm_name indicates the name of the RPM package.

   [root@xxx /]# cd $rpm_dir
   [root@xxx $rpm_dir]# rpm -ivh $rpm_name
   

   Note

   OceanBase Database will be installed in the /home/admin/oceanbase directory.

   Here is an example:

   [root@xxx /home/admin/rpm]# rpm -ivh oceanbase-4.2.0.0-100000052023073123.el7.x86_64.rpm
   Preparing...                          ################################# [100%]
   Updating / installing...
      1:oceanbase-4.2.0.0-100000052023073################################# [100%]
   

2. Install OceanBase Client.

   If an OceanBase instance is compatible with Oracle, you need to install the Java driver file (oceanbase-client-*.jar) provided by OceanBase Database for connecting Java applications. If you want to access an Oracle tenant from the command line, you also need to install OBClient.

   OBClient is an OceanBase command-line client that can access both MySQL and Oracle tenants of OceanBase Database.

   Here is an example:

   [root@xxx $rpm_dir]# rpm -ivh obclient-1.2.6-20210510164331.el7.alios7.x86_64.rpm
   
   ##Check whether OBClient has been installed.##
   [root@xxx $rpm_dir]# which obclient
   /usr/bin/obclient
   

Step 2: Configure directories

1. Clear the OceanBase directory (do not perform this step on the first deployment).

   If you want to clear the previous OceanBase environment or the environment is messed up or contains files that will affect the installation in the next time, you can directly clear the old OceanBase directory. In this case, you must specify the cluster name. $cluster_name indicates the cluster name.

   [root@xxx admin]# su - admin
   -bash-4.2$ kill -9 `pidof observer` 
   -bash-4.2$ rm -rf /data/1/$cluster_name 
   -bash-4.2$ rm -rf /data/log1/$cluster_name 
   -bash-4.2$ rm -rf /home/admin/oceanbase/store/$cluster_name /home/admin/oceanbase/log/* /home/admin/oceanbase/etc/*config*
   -bash-4.2$ ps -ef|grep observer
   

   Here is an example:

   [root@xxx admin]# su - admin
   -bash-4.2$ kill -9 `pidof observer` 
   -bash-4.2$ rm -rf /data/1/obdemo 
   -bash-4.2$ rm -rf /data/log1/obdemo 
   -bash-4.2$ rm -rf /home/admin/oceanbase/store/obdemo /home/admin/oceanbase/log/* /home/admin/oceanbase/etc/*config*
   -bash-4.2$ ps -ef|grep observer
   

2. Initialize the OceanBase directory.

   We recommend that you install the data directory of OceanBase Database on a separate disk and then use a soft link to link the data directory to the home directory of the software. In this way, the size of the software package can be reduced. In this step, $cluster_name indicates the cluster name.

   Note

   Starting from V4.3.0, OceanBase Database allows you to separate the slog from the data (data) disk. In other words, the slog and data files do not need to be on the same disk. You can configure the disks to share an SSD for slog and clog. For more information about the installation directories of OceanBase Database, see OBServer node installation directory structure.

   [root@xxx admin]# su - admin
   -bash-4.2$ mkdir -p /data/1/$cluster_name/{etc3,sstable,slog} 
   -bash-4.2$ mkdir -p /data/log1/$cluster_name/{clog,etc2} 
   -bash-4.2$ mkdir -p /home/admin/oceanbase/store/$cluster_name
   -bash-4.2$ for t in {etc3,sstable,slog};do ln -s /data/1/$cluster_name/$t /home/admin/oceanbase/store/$cluster_name/$t; done
   -bash-4.2$ for t in {clog,etc2};do ln -s /data/log1/$cluster_name/$t /home/admin/oceanbase/store/$cluster_name/$t; done
   

   Here is an example:

   [root@xxx admin]# su - admin
   -bash-4.2$ mkdir -p /data/1/obdemo/{etc3,sstable,slog} 
   -bash-4.2$ mkdir -p /data/log1/obdemo/{clog,etc2} 
   -bash-4.2$ mkdir -p /home/admin/oceanbase/store/obdemo
   -bash-4.2$ for t in {etc3,sstable,slog};do ln -s /data/1/obdemo/$t /home/admin/oceanbase/store/obdemo/$t; done
   -bash-4.2$ for t in {clog,etc2};do ln -s /data/log1/obdemo/$t /home/admin/oceanbase/store/obdemo/$t; done
   

   Note

   The obdemo directory is created based on the cluster name and can be customized. It is used by the startup process.

   The check result is as follows:

   -bash-4.2$ cd /home/admin/oceanbase
   -bash-4.2$ tree store/
   store/
   `-- obdemo
    |-- clog -> /data/log1/obdemo/clog
    |-- etc2 -> /data/log1/obdemo/etc2
    |-- etc3 -> /data/1/obdemo/etc3
    |-- slog -> /data/1/obdemo/slog
    `-- sstable -> /data/1/obdemo/sstable
   
   6 directories, 0 files
   

Step 3: Initialize the OceanBase cluster

1. Start the observer process.

   You must start the observer process as the admin user. The sample statement is as follows:

   cd /home/admin/oceanbase && /home/admin/oceanbase/bin/observer {-I $ip | -i $devname} -P $rpc_port -p $sql_port -z $zone_name -d /home/admin/oceanbase/store/$cluster_name -r '$ip:2882:2881' -c $cluster_id -n $cluster_name -o "system_memory=30G,datafile_size=500G,config_additional_dir=/data/1/$cluster_name/etc3;/data/log1/$cluster_name/etc2"
   

   The parameters are described as follows:

   Parameter	Description
   -I | -i	-I: the IP address of the node to be started. In a multi-server deployment scenario, 127.0.0.1 cannot be used as the target IP address. We recommend that you use the specified IP address (-I 10.10.10.1) to start a node. -i: the name of the network interface card. You can use the ifconfig command to view the network interface card names. Note You can start the node by specifying both the IP address and the network interface card name (for example, -I 10.10.10.1 -i eth0), but we recommend that you do not specify both parameters.
   -p	the service port number, which is generally set to 2881.
   -P	the RPC port number, which is generally set to 2882.
   -n	the cluster name. It can be customized as long as it is not repeated among different clusters.
   -z	the zone to which the observer process belongs.
   -d	the directory where the cluster is located. The directory is created when the cluster is initialized. Apart from the cluster name $cluster_name, other parameters should not be changed.
   -c	the cluster ID. It is a group of numbers and can be customized as long as it is not repeated among different clusters.
   -l	the log level.
   -r	the root service information in the format of $ip:2882:2881, which is separated with semicolons.
   -o	the list of cluster startup parameters (configurations). It is an optional parameter. You can specify values for multiple parameters, separating the values with commas. Choose appropriate startup parameters and specify proper values for each parameter to optimize the cluster's performance and resource utilization. Some common cluster startup configurations are described as follows: cpu_count: the total number of CPU cores. system_memory: the memory size reserved for tenant ID 500. In other words, it is the internal memory of OceanBase Database. If the system memory is limited, you can set the system_memory parameter to a smaller value. Note that during performance tests, the system may run out of memory. memory_limit: the total size of available memory. datafile_size: the size of disk space occupied by data files. In other words, it is the size of the sstable file of OceanBase Database. It is set based on the available space of /data/1/. We recommend that you set it to at least 100G. datafile_disk_percentage: the percentage of total disk space occupied by data files. datafile_next: the automatic expansion step length of disk data files. datafile_maxsize: the maximum space of automatic expansion of disk data files. config_additional_dir: multiple directories for storing local configuration files for redundancy. log_disk_size: the size of the redo log disk. log_disk_percentage: the percentage of total disk space occupied by the redo log. syslog_level: the system log level. syslog_io_bandwidth_limit: the maximum disk I/O bandwidth allowed for system logs. System logs exceeding the bandwidth limit will be discarded. max_syslog_file_count: the maximum number of log files that can be stored before the system starts to recycle logs. enable_syslog_recycle: the switch to enable log recycling. It is used in conjunction with the max_syslog_file_count parameter to determine whether to recycle old log files. The datafile_size, datafile_disk_percentage, datafile_next, and datafile_maxsize parameters are used to enable automatic expansion of disk data files. For more information, see Enable dynamic expansion for disk data files. For more information about cluster configurations, see Overview of cluster-level configurations.

   Here is an example:

   [root@xxx admin]# su - admin
   -bash-4.2$ cd /home/admin/oceanbase && /home/admin/oceanbase/bin/observer -I 10.10.10.1 -P 2882 -p 2881 -z zone1 -d /home/admin/oceanbase/store/obdemo -r '10.10.10.1:2882:2881' -c 10001 -n obdemo -o "system_memory=30G,datafile_size=500G,config_additional_dir=/data/1/obdemo/etc3;/data/log1/obdemo/etc2"
   

   Run the following command to check whether the observer process has started successfully:

   • Use the netstat -ntlp command. If the process has listened on the 2881 and 2882 ports, the process has started successfully.
   • Use the ps -ef|grep observer command to return the observer process information.

   Here is an example:

   -bash-4.2$ netstat -ntlp
   (Not all processes could be identified, non-owned process info
   will not be shown, you would have to be root to see it all.)
   Active Internet connections (only servers)
   Proto Recv-Q Send-Q Local Address           Foreign Address         State       PID/Program name
   tcp        0      0 0.0.0.0:2881            0.0.0.0:*               LISTEN      11113/observer
   tcp        0      0 0.0.0.0:2882            0.0.0.0:*               LISTEN      11113/observer
   ...        ...    ...                       ...                     ...         ...
   
   -bash-4.2$ ps -ef|grep observer
   admin    11113      0 43 17:58 ?        00:00:14 /home/admin/oceanbase/bin/observer -I 10.10.10.1 -P 2882 -p 2881 -z zone1 -d /home/admin/oceanbase/store/obdemo -r 10.10.10.1:2882:2881 -c 10001 -n obdemo -o system_memory=30G,datafile_size=500G,config_additional_dir=/data/1/obdemo/etc3;/data/log1/obdemo/etc2
   

2. Perform the bootstrap operation.

   Use OBClient to connect to the started observer process. The password is empty.

   [root@xxx admin]# obclient -h127.0.0.1 -uroot -P2881 -p******
   
   obclient> SET SESSION ob_query_timeout=1000000000;
   Query OK, 0 rows affected
   
   obclient> ALTER SYSTEM BOOTSTRAP ZONE 'zone1' SERVER '10.10.10.1:2882';
   Query OK, 0 rows affected
   

   Note

   If an error occurs when you perform this operation, check whether the startup parameters of the observer process and the directory permissions are correct and whether the log directory has sufficient space. If the node lacks memory resources, the initialization will fail. In this case, resolve the issues first, and then clear the OceanBase directory and start it again (see Clear the OceanBase directory (first time only) ).

3. Verify that the cluster has been initialized.

   After the cluster is initialized, execute the SHOW DATABASES; command to verify whether the oceanbase database is listed. If yes, the cluster has been initialized successfully.

4. Change the password.

   The password of the root user in the sys tenant is empty by default. Change the password after the initialization is completed.

   ALTER USER root IDENTIFIED BY '******';
   

Next steps

After the cluster is created, you can create user tenants as needed.

For more information about how to create a user tenant, see Create a tenant.

References

• Connect to an OceanBase tenant by using OBClient
• Overview of system configuration items
• ALTER USER
• Introduction to user tenants
• CREATE TENANT