# Step 4: Test MariaDB Enterprise Server
## Overview
This page details step 4 of the 7-step procedure "[Deploy Primary/Replica Topology](/docs/server/architecture/topologies/primary-replica.md)".
This step tests MariaDB Enterprise Server
Several actions require connection to MariaDB Enterprise Server. A command-line client (mariadb) was included with your ES installation. These instructions describe connection via Unix domain socket. Alternatively, a different client and connection method could be used.
Interactive commands are detailed. Alternatively, the described operations can be performed using automation.
## Test Enterprise Server Service
Use Systemd to test whether the MariaDB Enterprise Server service is running.
This action is performed **on each Enterprise Server node**.
Check if the MariaDB Enterprise Server service is running by executing the following:
```bash
$ systemctl status mariadb
```
If the service is not running on any node, start the service by executing the following on that node:
```bash
$ sudo systemctl start mariadb
```
## Test Local Client Connections
Use [mariadb Client](/docs/server/clients-and-utilities/mariadb-client.md) to test the local connection to the Enterprise Server node.
This action is performed **on each Enterprise Server node**:
```bash
$ sudo mariadb
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MariaDB connection id is 38
Server version: 11.4.5-3-MariaDB-Enterprise MariaDB Enterprise Server
Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.
Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.
MariaDB [(none)]>
```
The sudo command is used here to connect to the Enterprise Server node using the root\@localhost user account, which authenticates using the [unix\_socket](/docs/server/reference/plugins/authentication-plugins/authentication-plugin-unix-socket.md) authentication plugin. Other user accounts can be used by specifying the `--user` and `--password` command-line options.
## Test Replica Status
Use [SHOW REPLICA STATUS](/docs/server/reference/sql-statements/administrative-sql-statements/show/show-replica-status.md) to check that replication is running properly on the replica servers.
This action is performed **on each replica server**.
Execute the following:
```sql
SHOW REPLICA STATUS\G
*************************** 1. row ***************************
Slave_IO_State: Waiting for master to send event
Master_Host: 192.0.2.1
Master_User: repl
Master_Port: 3306
Connect_Retry: 60
Master_Log_File: mariadb-bin.000001
Read_Master_Log_Pos: 645
Relay_Log_File: li282-189-relay-bin.000002
Relay_Log_Pos: 946
Relay_Master_Log_File: mariadb-bin.000001
Slave_IO_Running: Yes
Slave_SQL_Running: Yes
Replicate_Do_DB:
Replicate_Ignore_DB:
Replicate_Do_Table:
Replicate_Ignore_Table:
Replicate_Wild_Do_Table:
Replicate_Wild_Ignore_Table:
Last_Errno: 0
Last_Error:
Skip_Counter: 0
Exec_Master_Log_Pos: 645
Relay_Log_Space: 1259
Until_Condition: None
Until_Log_File:
Until_Log_Pos: 0
Master_SSL_Allowed: No
Master_SSL_CA_File:
Master_SSL_CA_Path:
Master_SSL_Cert:
Master_SSL_Cipher:
Master_SSL_Key:
Seconds_Behind_Master: 0
Master_SSL_Verify_Server_Cert: No
Last_IO_Errno: 0
Last_IO_Error:
Last_SQL_Errno: 0
Last_SQL_Error:
Replicate_Ignore_Server_Ids:
Master_Server_Id: 1
Master_SSL_Crl:
Master_SSL_Crlpath:
Using_Gtid: Slave_Pos
Gtid_IO_Pos: 0-1-2
Replicate_Do_Domain_Ids:
Replicate_Ignore_Domain_Ids:
Parallel_Mode: optimistic
SQL_Delay: 0
SQL_Remaining_Delay: NULL
Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates
Slave_DDL_Groups: 2
Slave_Non_Transactional_Groups: 0
Slave_Transactional_Groups: 0
```
If `Slave_IO_Running` column is not `Yes` on any replica server, then check:
* The network connectivity between the replica server and the primary server
* The `Last_IO_Error` column for details on any errors
If `Slave_SQL_Running` column is not Yes on any replica server, then check:
* The GTID position in [gtid\_slave\_pos](/docs/server/ha-and-performance/standard-replication/gtid.md#gtid_slave_pos)
* The `Last_SQL_Error` column for details on any errors
If both columns are not `Yes` on any replica server, then check:
* The replication configuration on the replica server.
If you need to make any corrections, the slave threads can be restarted with [START REPLICA](/docs/server/reference/sql-statements/administrative-sql-statements/replication-statements/start-replica.md).
## Test DDL
Use [mariadb Client](/docs/server/clients-and-utilities/mariadb-client.md) to test DDL.
1. **On the primary server**, use the [mariadb Client](/docs/server/clients-and-utilities/mariadb-client.md) to connect to the node:
```bash
$ sudo mariadb
```
2. Create a test database and table:
```sql
CREATE DATABASE IF NOT EXISTS test;
CREATE TABLE test.contacts (
id INT PRIMARY KEY AUTO_INCREMENT,
first_name VARCHAR(50),
last_name VARCHAR(50),
email VARCHAR(100)
);
```
3. **On each replica server**, use the [mariadb Client](/docs/server/clients-and-utilities/mariadb-client.md) to connect to the node:
```bash
$ sudo mariadb
```
4. Confirm that the database and table exist:
```sql
SHOW CREATE TABLE test.contacts\G;
```
If the database or table do not exist on any node, then check the replication status on the node.
## Test DML
Use [mariadb Client](/docs/server/clients-and-utilities/mariadb-client.md) to test DML.
1. **On the primary server**, use the MariaDB Client to connect to the node:
```bash
$ sudo mariadb
```
2. Insert sample data into the table created in the DDL test:
```sql
INSERT INTO test.contacts (first_name, last_name, email)
VALUES
("Kai", "Devi", "kai.devi@example.com"),
("Lee", "Wang", "lee.wang@example.com");
```
3. **On each replica server**, use the [mariadb Client](/docs/server/clients-and-utilities/mariadb-client.md) to connect to the node:
```bash
$ sudo mariadb
```
4. Execute a [SELECT](/docs/server/reference/sql-statements/data-manipulation/selecting-data/select.md) query to retrieve the data:
```sql
SELECT * FROM test.contacts;
+----+------------+-----------+----------------------+
| id | first_name | last_name | email |
+----+------------+-----------+----------------------+
| 1 | Kai | Devi | kai.devi@example.com |
| 2 | Lee | Wang | lee.wang@example.com |
+----+------------+-----------+----------------------+
```
If the data is not returned on any node, then check the replication status on the node.
## Next Step
Navigation in the procedure "Deploy Primary/Replica Topology":
This page was step 4 of 7.
Next: Step 5: Install MariaDB MaxScale
*This page is: Copyright © 2025 MariaDB. All rights reserved.*
{% @marketo/form formId="4316" %}
---
# Agent Instructions: Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.
Perform an HTTP GET request on the current page URL with the `ask` query parameter:
```
GET https://mariadb.com/docs/server/architecture/topologies/primary-replica/step-4-test-mariadb-enterprise-server.md?ask=
```
The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.
Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.