MySQL Replication Status Test

Replication enables data from one MySQL database server (the source) to be copied to one or more MySQL database servers (the replicas). Replication is asynchronous by default; replicas do not need to be connected permanently to receive updates from the source. Depending on the configuration, you can replicate all databases, selected databases, or even selected tables within a database.

In a high availability environment, the replica servers should always be in sync with the master database instance. For this, the replication should always be enabled on the master and the replica servers should be connected to the master at all times. If the replication fails even for a brief period or if the replica servers are not connected to the master, the replica servers will not have the updated data. To avoid this, it is essential to monitor the replication status of the master MySQL database instance. The MySQL Replication Status test helps administrators in this regard!

This test reports whether/not the replication process is enabled on the target database instance and also helps administrators figure out if the target database instance is the master or not. Additionally, this test reports the count of slaves/replica servers connected to the target database instance and the current uptime of the database instance.

Target of the test : A MySQL server

Agent deploying the test : An internal/remote agent

Outputs of the test : One set of results for the target database server instance being monitored

Configurable parameters for the test
Parameter	Description
Test Period	How often should the test be executed.
Host	The IP address of the MySQL server.
Port	The port at which the specified host listens.
Database	Specify the name of a database on the target MySQL database server being monitored
Username and Password	The eG agent has to be configured with the credentials of a user who has server-wide Process and Select privileges on the monitored MySQL server. To know how to create such a user, refer to Pre-requisites for Monitoring the MySQL Server topic. For the MySQL Bin Log test to run, the user should additionally possess the following privileges. To configure the above-mentioned user with the specific privileges, issue the commands given below: GRANT REPLICATION CLIENT on . to '<username>'@'<IP_address_of_eG_agent>'; GRANT REPLICATION SLAVE on . to '<username>'@'<IP_address_of_eG_agent>'; GRANT EXECUTE on . to '<username>'@'<IP_address_of_eG_agent>';
Confirm Password	Confirm the password by retyping it here.
Allow Public Key	By default, the Allow Public Key flag is set to No. But, if the specified USER is created with caching_sha2_password as the authentication plugin, then the eG agent can connect to the target database cluster using RSA public key. To this effect, you have to set Allow Public Key flag to Yes.
SSL	By default, the SSL flag is set to No, indicating that the target MySQL database server is not SSL-enabled by default. To enable the test to connect to an SSL-enabled MySQL database server , set the SSL flag to Yes.
Verify CA	If the eG agent is required to establish an encrypted connection with the target MySQL database server by authenticating the server's identity through verifying the server CA certificate, set Verify CA flag to Yes. By default, this flag is set to No.
Truststore Password	This parameter is applicable only if the Verify CA parameter is set to Yes. To verify the target server certificate, provide the password of the truststore file which contains the server CA certificate in the Truststore Password text box. By default, this parameter is set to none.
Confirm Password	Confirm the Password by retyping it in the Confirm Password text box.
Keystore Password	This parameter is applicable only if the Verify CA parameter is set to Yes. To establish a connection with the target MySQL database server , the eG agent needs to have access to the client certificate. For this provide the password of the keystore file which contains the client certificate in the Keystore Password text box. By default, this parameter is set to none.
Confirm Password	Confirm the Password by retyping it in the Confirm Password text box.
Detailed Diagnosis	To make diagnosis more efficient and accurate, the eG Enterprise embeds an optional detailed diagnostic capability. With this capability, the eG agents can be configured to run detailed, more elaborate tests as and when specific problems are detected. To enable the detailed diagnosis capability of this test for a particular server, choose the On option. To disable the capability, click on the Off option. The option to selectively enable/disable the detailed diagnosis capability will be available only if the following conditions are fulfilled: The eG manager license should allow the detailed diagnosis capability Both the normal and abnormal frequencies configured for the detailed diagnosis measures should not be 0.

Measurements made by the test

Measurement

Description

Measurement Unit

Interpretation

Is replication enabled?

Indicates whether/not replication is enabled on the database instance.

The values reported by this measure and its numeric equivalents are mentioned in the table below:

Measure Value	Numeric Value
Yes	1
No	0

Note:

By default, this measure reports the Measure Values listed in the table above to indicate whether/not replication is enabled on this instance. The graph of this measure however, is represented using the numeric equivalents only i.e., 0 or 1.

Is master?

Indicates whether/not the database instance is the master.

The values reported by this measure and its numeric equivalents are mentioned in the table below:

Measure Value	Numeric Value
Yes	1
No	0

Note:

By default, this measure reports the Measure Values listed in the table above to indicate whether/not this instance is the master. The graph of this measure however, is represented using the numeric equivalents only i.e., 0 or 1.

Slave node count

Indicates the number of slaves/replica servers attached to the database instance.

Number

This measure will be reported only if the Is master? measure reports a value of Yes.

If the value of this measure decreases gradually, backup data could not be replicated by the master database instance and hence data could not be retrieved if the master database instance crashes.

Uptime

Indicates the current uptime of the database instance.

Minutes