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CLI - Database

Revision as of 09:39, 18 May 2021 by Shin (talk | contribs)

The imRAD use the MariaDB server[1]. We name it "mysql". In this wiki, you use both terms "MariaDB" and "mysql", but they are the same.

Verifying Database

If you run the show system mariadb command, it shows the version of the Database. To check the status of the database, enter the show service mysql or show service status mysql 

LYSH@MyHostName# show system mariadb
Database server               : 10.4.19-MariaDB, for debian-linux-gnu (x86_64)

LYSH@MyHostName# show service mysql
● mariadb.service - MariaDB 10.4.19 database server
     Loaded: loaded (/lib/systemd/system/mariadb.service; enabled; vendor preset: enabled)
    Drop-In: /etc/systemd/system/mariadb.service.d
             └─migrated-from-my.cnf-settings.conf
     Active: active (running) since Tue 2021-05-11 15:44:07 KST; 6 days ago
.....

Database Connection Properties

All Database Connection Properties are securely encrypted. If you want to see properties as plaintext, use the show database property {id} command.
The imRAD consists of three types of Database Connection Properties.

ID Name Description
0 MainDB It is the properties for imRAD main database. If there are two systems for the purpose of the System Failover, one of them is the main system. In other words, an active system is the main system and it has the main database.
2 LocalDB It is the properties for local database.
3 PeerDB If you configure the System Failover, these properties are written. If not, no properties for the type 3 exist.

Note that the leading five characters of the password are marked to * for the purpose of security. 

LYSH@MyHostName# show database property 0	// Display the database connection properties of the MainDB (1)
  Host:127.0.0.1
  Port:6710
  User-id:lyon
  User-Password:*****y@nu24

Configuring Database Connection Properties

You can configure the host of Database Connection Properties. However, you don't need to configure because If you configure the System Failover, the properties for other types are set automatically. Therefore, If there's no problem, DO NOT configure the Database Connection Properties. 

LYSH@MyHostName# configure	
configure# database property create 2 127.0.0.1	// Configuring the host of the LocalDB(2) to 127.0.0.1
configure# exit
LYSH@MyHostName# show database property 2	// Display the database connection properties of the LocalDB(2)

Configuring Database backup

You can configure to have the system can backup the database and the imRAD is already enabled to backup the database. The default configuration is

  • db_backup_interval=1
  • db_backup_hour=3
  • max_db_backup_file=5

The above configurations mean that the system backup the database at 3 o'clock every 1 day and remain only a recent 5 backup files. In other words, if there are more than 5 backup files after backup, the oldest one is removing. 

LYSH@MyHostName# show system db_backup		// view the current database backup configuration
db_backup task                : Active
db_backup                     : enable
db_backup_interval            : 1
db_backup_hour                : 3
max_db_backup_file            : 5
last_db_backup_datetime       : 2021-04-28 03:30:01
last_db_backup_state          : success

LYSH@MyHostName# configure
configure# database backup enable		// enable database backup
configure# database backup disable		// disable database backup
configure# database backup hour 5		// Configure the starting hour of database backup
configure# database backup interval 2		// Configure the database backup interval in days
configure# database backup maxfile 3		// Configure the maximum number of database backup files to keep

You can verify the current database backup configuration and backup files by the show database backup command 

LYSH@MyHostName# show database backup
db_backup task                : Active
db_backup                     : enable
db_backup_interval            : 1
db_backup_hour                : 3
max_db_backup_file            : 5
last_db_backup_datetime       : 2021-04-28 03:30:01
last_db_backup_state          : success

total 1.7M
-rw-r--r-- 1 root root   20 Apr 25 03:30 backup_210425.sql.gz
-rw-r--r-- 1 root root   20 Apr 26 03:30 backup_210426.sql.gz
-rw-r--r-- 1 root root   20 Apr 27 03:30 backup_210427.sql.gz
-rw-r--r-- 1 root root   20 Apr 28 03:30 backup_210428.sql.gz

Connect to Database(mysql)

You can access a database directly if necessary by the mysql command. If you want to access a database using "root", you must request an One Time Password (OTP)[2].

You should bear in mind that accessing the Database should be only for the purpose of maintenance or fixing problems.


Verifying Database

You can verify the status, variables, and so on by using the show database {ARG} command.

argument Description
backup It shows you the backup configuration and files.
connection It shows you information about which protocol is used.[3]
process It shows you which threads are running.[4]
  • ID: The client's process ID.
  • USER: The username associated with the process.
  • HOST: The host the client is connected to.
  • DB: The default database of the process (NULL if no default).
  • COMMAND: The command type. See Thread Command Values.
  • TIME: The amount of time, in seconds, the process has been in its current state.
  • INFO: The statement being executed.
  • PROGRESS: The total progress of the process (0-100%) (see Progress Reporting).
property It shows you decrypted database connection properties.
replication You can see the status of the MySQL replication.
status It shows you the status of MySQL service.
variable It shows you the MySQL global variables.

References

  1. ↑ https://en.wikipedia.org/wiki/MariaDB
  2. ↑ http://issue.basein.net
  3. ↑ https://mariadb.com/kb/en/mysql-command-line-client/
  4. ↑ https://mariadb.com/kb/en/show-processlist/