Basic Administration with MariaDB Xpand
This page outlines some frequently used utilities and tools available within Xpand.
Load Balancing Xpand
Xpand requires an external TCP load balancer to evenly distribute load across the cluster.
Accessing Xpand from the Command Line
To access Xpand from the command line, run MySQL from a command line prompt.
shell> mysql sql> SELECT * FROM test.sample ORDER BY birth; +------------+------------+------------+-----+ | name | birth | death | sex | +------------+------------+------------+-----+ | Rowinsky | 1952-08-01 | NULL | F | | Snyder | 1955-11-26 | 2014-05-17 | M | | Thompson | 1965-03-09 | NULL | F | | Johnson | 1980-06-11 | NULL | M | +------------+------------+------------+-----+ 4 rows in set (0.00 sec)
Because Xpand is MySQL compatible, many third party tools such as MySQLWorkbench, TOAD, etc. will work seamlessly with Xpand.
For additional information, see "Connect and Query".
Loading Data onto Xpand
Depending on your specific needs, there are numerous options for loading data onto Xpand:
Xpand recommends using clustrix_
importif your source database is MySQL or you have a
mysqldumpfile available. This is the fastest method for loading data onto Xpand from another system.
To cut over a production environment from MySQL to Xpand, you can use MySQL replication as outlined in "Migrate from MySQL to MariaDB Xpand".
To transfer user accounts and permissions, use
clustrix_clone_usersas documented in "Migrate User Permissions to MariaDB Xpand".
Load Data Infile can also be used to import data directly to Xpand from a csv file.
For additional information, see "Data Import with MariaDB Xpand".
Web-based Cluster Administration
Xpand includes XpandGUI Administration UI for cluster administration.
For additional information, see "XpandGUI for MariaDB Xpand".
Examining Xpand Server Logs
Xpand's server logs enable users and Customer Support to understand the queries and events that occur on a Xpand cluster. All the logs created by Xpand are placed, by default, in the
/data/clustrix/log directory (this is configurable) and there are a separate set of logs for each node of your cluster. The logs used most frequently are
query.log shows information for SQL statements used within Xpand. From the
query.log you can identify slow queries as well as query syntax errors. For additional information, see "Query Logging for MariaDB Xpand".
clustrix.log is a chronology of events that occur on your cluster. It includes alerts that are also logged to a separate log file -
alert.log. Please see "Email Alerts for MariaDB Xpand" to establish the necessary alerts for your cluster.
For additional information, see "Logs".
Using CLX - Cluster-Wide Command Line Utility
Xpand includes a general-purpose command line utility called
clx for monitoring and managing a cluster. A single
clx command is automatically processed in parallel on all nodes of a cluster. It is located in the
The full list of
clx commands and options are outlined in The CLX Command-Line Administration Tool. These commands are likely to be the most useful.
Useful CLX Commands
Displays the status, IP, and disk utilization of each node in a cluster.
Runs Linux commands in parallel on all nodes of the cluster.
Consolidates and filters Xpand logs so database issues can be researched and resolved.
Stops Xpand on all nodes.
Starts Xpand on all nodes.
Restarts Xpand on all nodes. (Use in lieu of
clx utility also communicates with another critical element of the system called
nanny is a database cluster process that provides monitoring to ensure that all processes vital to Xpand node functionality are running. It is activated at system startup. If any critical Xpand component fails at any point, for any reason,
nanny restarts it automatically.
For a list of the processes that
nanny monitors and controls, please refer to this "
nanny Overview for MariaDB Xpand".
Monitoring Xpand Using statd
Performance statistics are automatically collected by
statd in the
clustrix_statd database. The resulting statistics can be assessed by querying the tables directly or by viewing them with the XpandGUI administrative tool.
For a recap of the statistics gathered and some potential ways to analyze them, see "Monitoring with
statd for MariaDB Xpand".
Xpand regularly provides both major and minor releases to continuously improve its product's performance, functionality, scalability, and stability. Each release passes a thorough and rigorous quality assurance process before it is released to our customers.
For specifics on how to upgrade Xpand, see "Upgrades for MariaDB Xpand".
Expanding/Reducing Your Cluster's Capacity
Your application and database may experience fluctuating transaction volumes due to seasonal changes. The underlying design of Xpand enables it to easily and uniquely adapt to those changes. To increase your cluster's capacity, simply add more nodes. Conversely, if transaction volume subsequently declines, removing nodes to decrease costs is equally painless.
Parallel Backup and Restore
Xpand includes a fast parallel backup and restore feature. For backups, each Xpand node sends its data directly to the backup target in parallel, allowing for concurrency and for backup performance to scale with cluster size. Similarly, the restore operation is initiated on one node and that node coordinates with all other nodes of the cluster to read from the backup file and restore data throughout the cluster in parallel.
The Xpand database backups contain schema definitions, metadata relative to the backup, compacted row data, and information to ensure data consistency.
For additional information, see "Fast Backup and Restore with MariaDB Xpand".