Dba Class Reference

InnoDB Cluster, ReplicaSet, and ClusterSet management functions. More...

Methods
JSON	check_instance_configuration (InstanceDef instance, dict options)
	Validates an instance for MySQL InnoDB Cluster usage. More...
None	configure_replica_set_instance (InstanceDef instance, dict options)
	Validates and configures an instance for use in an InnoDB ReplicaSet. More...
None	configure_instance (InstanceDef instance, dict options)
	Validates and configures an instance for MySQL InnoDB Cluster usage. More...
Cluster	create_cluster (str name, dict options)
	Creates a MySQL InnoDB Cluster. More...
ReplicaSet	create_replica_set (str name, dict options)
	Creates a MySQL InnoDB ReplicaSet. More...
None	delete_sandbox_instance (int port, dict options)
	Deletes an existing MySQL Server instance on localhost. More...
Instance	deploy_sandbox_instance (int port, dict options)
	Creates a new MySQL Server instance on localhost. More...
None	drop_metadata_schema (dict options)
	Drops the Metadata Schema. More...
Cluster	get_cluster (str name)
	Returns an object representing a Cluster. More...
ClusterSet	get_cluster_set ()
	Returns an object representing a ClusterSet. More...
ReplicaSet	get_replica_set ()
	Returns an object representing a ReplicaSet. More...
None	kill_sandbox_instance (int port, dict options)
	Kills a running MySQL Server instance on localhost. More...
Cluster	reboot_cluster_from_complete_outage (str clusterName, dict options)
	Brings a cluster back ONLINE when all members are OFFLINE. More...
None	start_sandbox_instance (int port, dict options)
	Starts an existing MySQL Server instance on localhost. More...
None	stop_sandbox_instance (int port, dict options)
	Stops a running MySQL Server instance on localhost. More...
None	upgrade_metadata (dict options)
	Upgrades (or restores) the metadata to the version supported by the Shell. More...

Properties
int	verbose
	Controls debug message verbosity for sandbox related dba operations. More...
Session	session
	The session the dba object will use by default. More...

Detailed Description

InnoDB Cluster, ReplicaSet, and ClusterSet management functions.

Member Function Documentation

check_instance_configuration()

JSON check_instance_configuration	(	InstanceDef	instance,
		dict	options
	)

Validates an instance for MySQL InnoDB Cluster usage.

Parameters

instance	An instance definition.
options	Optional data for the operation.

Returns

A descriptive text of the operation result.

This function reviews the instance configuration to identify if it is valid for usage with group replication. Use this to check for possible configuration issues on MySQL instances before creating a cluster with them or adding them to an existing cluster.

The instance definition is the connection data for the instance.

For additional information about MySQL connection data, see Connection Data.

The options dictionary may contain the following options:

• mycnfPath: Optional path to the MySQL configuration file for the instance. Alias for verifyMyCnf
• verifyMyCnf: Optional path to the MySQL configuration file for the instance. If this option is given, the configuration file will be verified for the expected option values, in addition to the global MySQL system variables.

The returned descriptive text of the operation result indicates whether the instance is valid for InnoDB Cluster usage or not. If not, a table containing the following information is presented:

• Variable: the invalid configuration variable.
• Current Value: the current value for the invalid configuration variable.
• Required Value: the required value for the configuration variable.
• Note: the action to be taken.

The note can be one of the following:

• Update the config file and update or restart the server variable.
• Update the config file and restart the server.
• Update the config file.
• Update the server variable.
• Restart the server.

configure_replica_set_instance()

None configure_replica_set_instance	(	InstanceDef	instance,
		dict	options
	)

Validates and configures an instance for use in an InnoDB ReplicaSet.

Parameters

instance	Optional An instance definition. By default, the active shell session is used.
options	Optional Additional options for the operation.

Returns

Nothing

This function will verify and automatically configure the target instance for use in an InnoDB ReplicaSet.

The function can optionally create a "cluster administrator" account, if the "clusterAdmin" and "clusterAdminPassword" options are given. The account is created with the minimal set of privileges required to manage InnoDB clusters or ReplicaSets. The "cluster administrator" account must have matching username and password across all instances of the same cluster or replicaset.

Options

The instance definition is the connection data for the instance.

For additional information about MySQL connection data, see Connection Data.

The options dictionary may contain the following options:

• clusterAdmin: The name of a "cluster administrator" user to be created. The supported format is the standard MySQL account name format.
• clusterAdminPassword: The password for the "cluster administrator" account.
• clusterAdminPasswordExpiration: Password expiration setting for the account. May be set to the number of days for expiration, 'NEVER' to disable expiration and 'DEFAULT' to use the system default.
• clusterAdminCertIssuer: Optional SSL certificate issuer for the account.
• clusterAdminCertSubject: Optional SSL certificate subject for the account.
• restart: boolean value used to indicate that a remote restart of the target instance should be performed to finalize the operation.
• applierWorkerThreads: Number of threads used for applying replicated transactions. The default value is 4.

This function reviews the instance configuration to identify if it is valid for usage in replicasets. An exception is thrown if not.

If the instance was not valid for InnoDB ReplicaSet and interaction is enabled, before configuring the instance a prompt to confirm the changes is presented and a table with the following information:

• Variable: the invalid configuration variable.
• Current Value: the current value for the invalid configuration variable.
• Required Value: the required value for the configuration variable.

configure_instance()

None configure_instance	(	InstanceDef	instance,
		dict	options
	)

Validates and configures an instance for MySQL InnoDB Cluster usage.

Parameters

instance	Optional An instance definition.
options	Optional Additional options for the operation.

Returns

A descriptive text of the operation result.

This function auto-configures the instance for InnoDB Cluster usage. If the target instance already belongs to an InnoDB Cluster it errors out.

The instance definition is the connection data for the instance.

For additional information about MySQL connection data, see Connection Data.

The options dictionary may contain the following options:

• mycnfPath: The path to the MySQL configuration file of the instance.
• outputMycnfPath: Alternative output path to write the MySQL configuration file of the instance.
• clusterAdmin: The name of the "cluster administrator" account.
• clusterAdminPassword: The password for the "cluster administrator" account.
• clusterAdminPasswordExpiration: Password expiration setting for the account. May be set to the number of days for expiration, 'NEVER' to disable expiration and 'DEFAULT' to use the system default.
• clusterAdminCertIssuer: Optional SSL certificate issuer for the account.
• clusterAdminCertSubject: Optional SSL certificate subject for the account.
• restart: boolean value used to indicate that a remote restart of the target instance should be performed to finalize the operation.

• applierWorkerThreads: Number of threads used for applying replicated transactions. The default value is 4.

If the outputMycnfPath option is used, only that file is updated and mycnfPath is treated as read-only.

The clusterAdmin must be a standard MySQL account name. It could be either an existing account or an account to be created.

The clusterAdminPassword must be specified only if the clusterAdmin account will be created.

This function reviews the instance configuration to identify if it is valid for usage in group replication and cluster. An exception is thrown if not.

If the instance was not valid for InnoDB Cluster and interaction is enabled, before configuring the instance a prompt to confirm the changes is presented and a table with the following information:

• Variable: the invalid configuration variable.
• Current Value: the current value for the invalid configuration variable.
• Required Value: the required value for the configuration variable.

create_cluster()

Cluster create_cluster	(	str	name,
		dict	options
	)

Creates a MySQL InnoDB Cluster.

Parameters

name	An identifier for the Cluster to be created.
options	Optional dictionary with additional parameters described below.

Returns

The created Cluster object.

Creates a MySQL InnoDB Cluster taking as seed instance the server the shell is currently connected to.

The options dictionary can contain the following values:

• disableClone: boolean value used to disable the clone usage on the Cluster.
• gtidSetIsComplete: boolean value which indicates whether the GTID set of the seed instance corresponds to all transactions executed. Default is false.
• multiPrimary: boolean value used to define an InnoDB Cluster with multiple writable instances.
• force: boolean, confirms that the multiPrimary option must be applied and/or the operation must proceed even if unmanaged replication channels were detected.
• adoptFromGR: boolean value used to create the InnoDB Cluster based on existing replication group.
• memberSslMode: SSL mode for communication channels opened by Group Replication from one server to another.
• memberAuthType: controls the authentication type to use for the internal replication accounts.
• certIssuer: common certificate issuer to use when 'memberAuthType' contains one of the four "CERT_*" values
• certSubject: instance's certificate subject to use when 'memberAuthType' contains "CERT_SUBJECT" or "CERT_SUBJECT_PASSWORD".
• ipAllowlist: The list of hosts allowed to connect to the instance for group replication. Only valid if communicationStack=XCOM.
• groupName: string value with the Group Replication group name UUID to be used instead of the automatically generated one.
• localAddress: string value with the Group Replication local address to be used instead of the automatically generated one.
• manualStartOnBoot: boolean (default false). If false, Group Replication in Cluster instances will automatically start and rejoin when MySQL starts, otherwise it must be started manually.
• replicationAllowedHost: string value to use as the host name part of internal replication accounts (i.e. 'mysql_innodb_cluster_###'@'hostname'). Default is %. It must be possible for any member of the Cluster to connect to any other member using accounts with this hostname value.
• exitStateAction: string value indicating the group replication exit state action.
• memberWeight: integer value with a percentage weight for automatic primary election on failover.
• consistency: string value indicating the consistency guarantees that the cluster provides.
• expelTimeout: integer value to define the time period in seconds that cluster members should wait for a non-responding member before evicting it from the cluster.
• autoRejoinTries: integer value to define the number of times an instance will attempt to rejoin the cluster after being expelled.
• communicationStack: The Group Replication communication stack to be used in the Cluster: XCom (legacy) or MySQL.
• transactionSizeLimit: integer value to configure the maximum transaction size in bytes which the Cluster accepts
• paxosSingleLeader: boolean value used to enable/disable the Group Communication engine to operate with a single consensus leader.

An InnoDB Cluster may be setup in two ways:

• Single Primary: One member of the Cluster allows write operations while the rest are read-only secondaries.
• Multi Primary: All the members in the Cluster allow both read and write operations.

Note that Multi-Primary mode has limitations about what can be safely executed. Make sure to read the MySQL documentation for Group Replication and be aware of what is and is not safely executable in such setups.

By default this function creates a Single Primary Cluster. Use the multiPrimary option set to true if a Multi Primary Cluster is required.

The Cluster's name must be non-empty and no greater than 63 characters long. It can only start with an alphanumeric character or with _ (underscore), and can only contain alphanumeric, _ ( underscore), . (period), or - (hyphen) characters.

Options

disableClone should be set to true if built-in clone support should be completely disabled, even in instances where that is supported. Built-in clone support is available starting with MySQL 8.0.17 and allows automatically provisioning new Cluster members by copying state from an existing Cluster member. Note that clone will completely delete all data in the instance being added to the Cluster.

gtidSetIsComplete is used to indicate that GTIDs have been always enabled at the Cluster seed instance and that GTID_EXECUTED contains all transactions ever executed. It must be left as false if data was inserted or modified while GTIDs were disabled or if RESET MASTER was executed. This flag affects how Cluster.add_instance() decides which recovery methods are safe to use. Distributed recovery based on replaying the transaction history is only assumed to be safe if the transaction history is known to be complete, otherwise Cluster members could end up with incomplete data sets.

adoptFromGR allows creating an InnoDB Cluster from an existing unmanaged Group Replication setup, enabling use of MySQL Router and the shell AdminAPI for managing it.

The memberSslMode option controls whether TLS is to be used for connections opened by Group Replication from one server to another (both recovery and group communication, in either communication stack). It also controls what kind of verification the client end of connections perform on the SSL certificate presented by the server end.

The memberSslMode option supports the following values:

• REQUIRED: if used, SSL (encryption) will be enabled for the instances to communicate with other members of the cluster
• VERIFY_CA: Like REQUIRED, but additionally verify the peer server TLS certificate against the configured Certificate Authority (CA) certificates.
• VERIFY_IDENTITY: Like VERIFY_CA, but additionally verify that the peer server certificate matches the host to which the connection is attempted.
• DISABLED: if used, SSL (encryption) will be disabled
• AUTO: if used, SSL (encryption) will be enabled if supported by the instance, otherwise disabled

If memberSslMode is not specified AUTO will be used by default.

The memberAuthType option supports the following values:

• PASSWORD: account authenticates with password only.
• CERT_ISSUER: account authenticates with client certificate, which must match the expected issuer (see 'certIssuer' option).
• CERT_SUBJECT: account authenticates with client certificate, which must match the expected issuer and subject (see 'certSubject' option).
• CERT_ISSUER_PASSWORD: combines both "CERT_ISSUER" and "PASSWORD" values.
• CERT_SUBJECT_PASSWORD: combines both "CERT_SUBJECT" and "PASSWORD" values.

If memberAuthType is not specified, "PASSWORD" will be used by default.

When CERT_ISSUER or CERT_SUBJECT are used, the server's own certificate is used as its client certificate when authenticating replication channels with peer servers. memberSslMode must be at least REQUIRED, although VERIFY_CA or VERIFY_IDENTITY are recommended for additional security.

The ipAllowlist format is a comma separated list of IP addresses or subnet CIDR notation, for example: 192.168.1.0/24,10.0.0.1. By default the value is set to AUTOMATIC, allowing addresses from the instance private network to be automatically set for the allowlist.

This option is only used and allowed when communicationStack is set to XCOM.

The groupName and localAddress are advanced options and their usage is discouraged since incorrect values can lead to Group Replication errors.

The value for groupName is used to set the Group Replication system variable 'group_replication_group_name'.

The value for localAddress is used to set the Group Replication system variable 'group_replication_local_address'. The localAddress option accepts values in the format: 'host:port' or 'host:' or ':port'. If the specified value does not include a colon (:) and it is numeric, then it is assumed to be the port, otherwise it is considered to be the host. When the host is not specified, the default value is the value of the system variable 'report_host' if defined (i.e., not 'NULL'), otherwise it is the hostname value. When the port is not specified, the default value is the port of the target instance if the communication stack in use by the Cluster is 'MYSQL', otherwise, port * 10 + 1 when the communication stack is 'XCOM'. In case the automatically determined default port value is invalid (> 65535) then an error is thrown.

The exitStateAction option supports the following values:

• ABORT_SERVER: if used, the instance shuts itself down if it leaves the cluster unintentionally or exhausts its auto-rejoin attempts.
• READ_ONLY: if used, the instance switches itself to super-read-only mode if it leaves the cluster unintentionally or exhausts its auto-rejoin attempts.
• OFFLINE_MODE: if used, the instance switches itself to offline mode if it leaves the cluster unintentionally or exhausts its auto-rejoin attempts. Requires MySQL 8.0.18 or newer.

If exitStateAction is not specified, it defaults to OFFLINE_MODE for server versions 8.4.0 or newer, and READ_ONLY otherwise.

The consistency option supports the following values:

• BEFORE_ON_PRIMARY_FAILOVER: if used, new queries (read or write) to the new primary will be put on hold until after the backlog from the old primary is applied.
• EVENTUAL: if used, read queries to the new primary are allowed even if the backlog isn't applied.

If consistency is not specified, it defaults to BEFORE_ON_PRIMARY_FAILOVER for server versions 8.4.0 or newer, and EVENTUAL otherwise.

The value for exitStateAction is used to configure how Group Replication behaves when a server instance leaves the group unintentionally (for example after encountering an applier error) or exhausts its auto-rejoin attempts. When set to ABORT_SERVER, the instance shuts itself down. When set to READ_ONLY the server switches itself to super-read-only mode. When set to OFFLINE_MODE it switches itself to offline mode. In this mode, connected client users are disconnected on their next request and connections are no longer accepted, with the exception of client users that have the CONNECTION_ADMIN or SUPER privilege. The exitStateAction option accepts case-insensitive string values, being the accepted values: OFFLINE_MODE (or 2), ABORT_SERVER (or 1) and READ_ONLY (or 0).

The default value is OFFLINE_MODE for server versions 8.4.0 or newer, and READ_ONLY otherwise.

The value for memberWeight is used to set the Group Replication system variable 'group_replication_member_weight'. The memberWeight option accepts integer values. Group Replication limits the value range from 0 to 100, automatically adjusting it if a lower/bigger value is provided.

Group Replication uses a default value of 50 if no value is provided.

The value for consistency is used to set the Group Replication system variable 'group_replication_consistency' and configure the transaction consistency guarantee which a cluster provides.

When set to BEFORE_ON_PRIMARY_FAILOVER, whenever a primary failover happens in single-primary mode (default), new queries (read or write) to the newly elected primary that is applying backlog from the old primary, will be hold before execution until the backlog is applied. Special care is needed if LOCK / UNLOCK queries are used in a secondary, because the UNLOCK statement can be held. This means that, if the secondary is promoted, and transactions from the primary are being applied that target locked tables, they won't be applied and an explicit UNLOCK will also hold because the secondary needs to finish applying the transactions from the previous primary. See https://dev.mysql.com/doc/refman/en/group-replication-system-variables.html#sysvar_group_replication_consistency for more details.

When set to EVENTUAL, read queries to the new primary are allowed even if the backlog isn't applied but writes will fail (if the backlog isn't applied) due to super-read-only mode being enabled. The client may return old values.

When set to BEFORE, each transaction (RW or RO) waits until all preceding transactions are complete before starting its execution. This ensures that each transaction is executed on the most up-to-date snapshot of the data, regardless of which member it is executed on. The latency of the transaction is affected but the overhead of synchronization on RW transactions is reduced since synchronization is used only on RO transactions.

When set to AFTER, each RW transaction waits until its changes have been applied on all of the other members. This ensures that once this transaction completes, all following transactions read a database state that includes its changes, regardless of which member they are executed on. This mode shall only be used on a group that is used for predominantly RO operations to ensure that subsequent reads fetch the latest data which includes the latest writes. The overhead of synchronization on every RO transaction is reduced since synchronization is used only on RW transactions.

When set to BEFORE_AND_AFTER, each RW transaction waits for all preceding transactions to complete before being applied and until its changes have been applied on other members. A RO transaction waits for all preceding transactions to complete before execution takes place. This ensures the guarantees given by BEFORE and by AFTER. The overhead of synchronization is higher.

The consistency option accepts case-insensitive string values, being the accepted values: EVENTUAL (or 0), BEFORE_ON_PRIMARY_FAILOVER (or 1), BEFORE (or 2), AFTER (or 3), and BEFORE_AND_AFTER (or 4).

It defaults to BEFORE_ON_PRIMARY_FAILOVER for server versions 8.4.0 or newer, and EVENTUAL otherwise.

The value for expelTimeout is used to set the Group Replication system variable 'group_replication_member_expel_timeout' and configure how long Group Replication will wait before expelling from the group any members suspected of having failed. On slow networks, or when there are expected machine slowdowns, increase the value of this option. The expelTimeout option accepts positive integer values and, since 8.0.21, defaults to 5 seconds.

The value for autoRejoinTries is used to set the Group Replication system variable 'group_replication_autorejoin_tries' and configure how many times an instance will try to rejoin a Group Replication group after being expelled. In scenarios where network glitches happen but recover quickly, setting this option prevents users from having to manually add the expelled node back to the group. The autoRejoinTries option accepts positive integer values and, since 8.0.21, defaults to 3.

The value for communicationStack is used to choose which Group Replication communication stack must be used in the Cluster. It's used to set the value of the Group Replication system variable 'group_replication_communication_stack'.

When set to legacy 'XCom', all internal GCS network traffic (PAXOS and communication infrastructure) flows through a separate network address: the localAddress.

When set to 'MySQL', such traffic re-uses the existing MySQL Server facilities to establish connections among Cluster members. It allows a simpler and safer setup as it obsoletes the usage of IP allowlists (ipAllowlist), removes the explicit need to have a separate network address (localAddress), and introduces user-based authentication.

The default value for Clusters running 8.0.27+ is 'MySQL'.

The value for transactionSizeLimit is used to set the Group Replication system variable 'group_replication_transaction_size_limit' and configures the maximum transaction size in bytes which the Cluster accepts. Transactions larger than this size are rolled back by the receiving member and are not broadcast to the Cluster.

The transactionSizeLimit option accepts positive integer values and, if set to zero, there is no limit to the size of transactions the Cluster accepts

All members added or rejoined to the Cluster will use the same value.

The value for paxosSingleLeader is used to enable or disable the Group Communication engine to operate with a single consensus leader when the Cluster is in single-primary more. When enabled, the Cluster uses a single leader to drive consensus which improves performance and resilience in single-primary mode, particularly when some of the Cluster's members are unreachable.

The option is available on MySQL 8.0.31 or newer and the default value is 'OFF'.

create_replica_set()

ReplicaSet create_replica_set	(	str	name,
		dict	options
	)

Creates a MySQL InnoDB ReplicaSet.

Parameters

name	An identifier for the ReplicaSet to be created.
options	Optional dictionary with additional parameters described below.

Returns

The created ReplicaSet object.

This function will create a managed ReplicaSet using MySQL asynchronous replication, as opposed to Group Replication. The MySQL instance the shell is connected to will be the initial PRIMARY of the ReplicaSet. The replication channel will have TLS encryption enabled by default.

The function will perform several checks to ensure the instance state and configuration are compatible with a managed ReplicaSet and if so, a metadata schema will be initialized there.

New replica instances can be added through the add_instance() function of the returned ReplicaSet object. Status of the instances and their replication channels can be inspected with status().

InnoDB ReplicaSets

A ReplicaSet allows managing a GTID-based MySQL replication setup, in a single PRIMARY/multiple SECONDARY topology.

A ReplicaSet has several limitations compared to a InnoDB cluster and thus, it is recommended that InnoDB clusters be preferred unless not possible. Generally, a ReplicaSet on its own does not provide High Availability. Among its limitations are:

• No automatic failover
• No protection against inconsistencies or partial data loss in a crash

Pre-Requisites

The following is a non-exhaustive list of requirements for managed ReplicaSets. The dba.configure_instance() command can be used to make necessary configuration changes automatically.

• MySQL 8.0 or newer required
• Statement Based Replication (SBR) is unsupported, only Row Based Replication
• GTIDs required
• Replication filters are not allowed
• All instances in the ReplicaSet must be managed
• Unmanaged replication channels are not allowed in any instance

The ReplicaSet's name must be non-empty and no greater than 63 characters long. It can only start with an alphanumeric character or with _ (underscore), and can only contain alphanumeric, _ ( underscore), . (period), or - ( hyphen) characters.

Adopting an Existing Topology

Existing asynchronous setups can be managed by calling this function with the adoptFromAR option. The topology will be automatically scanned and validated, starting from the instance the shell is connected to, and all instances that are part of the topology will be automatically added to the ReplicaSet.

The only changes made by this function to an adopted ReplicaSet are the creation of the metadata schema. Existing replication channels will not be changed during adoption, although they will be changed during PRIMARY switch operations.

However, it is only possible to manage setups that use supported configurations and topology. Configuration of all instances will be checked during adoption, to ensure they are compatible. All replication channels must be active and their transaction sets as verified through GTID sets must be consistent. The data set of all instances are expected to be identical, but is not verified.

Options

The options dictionary can contain the following values:

• adoptFromAR: boolean value used to create the ReplicaSet based on an existing asynchronous replication setup.
• instanceLabel: string a name to identify the target instance. Defaults to hostname:port
• dryRun: boolean if true, all validations and steps for creating a replica set are executed, but no changes are actually made. An exception will be thrown when finished.
• gtidSetIsComplete: boolean value which indicates whether the GTID set of the seed instance corresponds to all transactions executed. Default is false.
• replicationAllowedHost: string value to use as the host name part of internal replication accounts (i.e. 'mysql_innodb_rs_###'@'hostname'). Default is %. It must be possible for any member of the ReplicaSet to connect to any other member using accounts with this hostname value.
• memberAuthType: controls the authentication type to use for the internal replication accounts.
• certIssuer: common certificate issuer to use when 'memberAuthType' contains one of the four "CERT_*" values
• certSubject: instance's certificate subject to use when 'memberAuthType' contains "CERT_SUBJECT" or "CERT_SUBJECT_PASSWORD".
• replicationSslMode: SSL mode to use to configure the asynchronous replication channels of the ReplicaSet.

The replicationSslMode option supports the following values:

• DISABLED: TLS encryption is disabled for the replication channel.
• REQUIRED: TLS encryption is enabled for the replication channel.
• VERIFY_CA: like REQUIRED, but additionally verify the peer server TLS certificate against the configured Certificate Authority (CA) certificates.
• VERIFY_IDENTITY: like VERIFY_CA, but additionally verify that the peer server certificate matches the host to which the connection is attempted.
• AUTO: TLS encryption will be enabled if supported by the instance, otherwise disabled.

If replicationSslMode is not specified AUTO will be used by default.

The memberAuthType option supports the following values:

• PASSWORD: account authenticates with password only.
• CERT_ISSUER: account authenticates with client certificate, which must match the expected issuer (see 'certIssuer' option).
• CERT_SUBJECT: account authenticates with client certificate, which must match the expected issuer and subject (see 'certSubject' option).
• CERT_ISSUER_PASSWORD: combines both "CERT_ISSUER" and "PASSWORD" values.
• CERT_SUBJECT_PASSWORD: combines both "CERT_SUBJECT" and "PASSWORD" values.

If memberAuthType is not specified, "PASSWORD" will be used by default.

When CERT_ISSUER or CERT_SUBJECT are used, the server's own certificate is used as its client certificate when authenticating replication channels with peer servers. replicationSslMode must be at least REQUIRED, although VERIFY_CA or VERIFY_IDENTITY are recommended for additional security.

delete_sandbox_instance()

None delete_sandbox_instance	(	int	port,
		dict	options
	)

Deletes an existing MySQL Server instance on localhost.

Parameters

port	The port of the instance to be deleted.
options	Optional dictionary with options that modify the way this function is executed.

Returns

Nothing.

This function will delete an existing MySQL Server instance on the local host. The following options affect the result:

• sandboxDir: path where the instance is located.

The sandboxDir must be the one where the MySQL instance was deployed. If not specified it will use:

~/mysql-sandboxes on Unix-like systems or %userprofile%\MySQL\mysql-sandboxes on Windows systems.

If the instance is not located on the used path an error will occur.

deploy_sandbox_instance()

Instance deploy_sandbox_instance	(	int	port,
		dict	options
	)

Creates a new MySQL Server instance on localhost.

Parameters

port	The port where the new instance will listen for connections.
options	Optional dictionary with options affecting the new deployed instance.

Returns

Nothing.

This function will deploy a new MySQL Server instance, the result may be affected by the provided options:

• portx: port where the new instance will listen for X Protocol connections.
• sandboxDir: path where the new instance will be deployed.
• password: password for the MySQL root user on the new instance.
• allowRootFrom: create remote root account, restricted to the given address pattern (default: %).
• ignoreSslError: ignore errors when adding SSL support for the new instance, by default: true.
• mysqldOptions: list of MySQL configuration options to write to the my.cnf file, as option=value strings.

If the portx option is not specified, it will be automatically calculated as 10 times the value of the provided MySQL port.

The password option specifies the MySQL root password on the new instance.

The sandboxDir must be an existing folder where the new instance will be deployed. If not specified the new instance will be deployed at:

~/mysql-sandboxes on Unix-like systems or %userprofile%\MySQL\mysql-sandboxes on Windows systems.

SSL support is added by default if not already available for the new instance, but if it fails to be added then the error is ignored. Set the ignoreSslError option to false to ensure the new instance is deployed with SSL support.

drop_metadata_schema()

None drop_metadata_schema

(

dict

options

)

Drops the Metadata Schema.

Parameters

options

Dictionary containing an option to confirm the drop operation.

Returns

Nothing.

The options dictionary may contain the following options:

• force: boolean, confirms that the drop operation must be executed.

get_cluster()

Cluster get_cluster

(

str

name

)

Returns an object representing a Cluster.

Parameters

name	Optional parameter to specify the name of the Cluster to be returned.

Returns

The Cluster object identified by the given name or the default Cluster.

If name is not specified or is null, the default Cluster will be returned.

If name is specified, and no Cluster with the indicated name is found, an error will be raised.

get_cluster_set()

std::shared_ptr< ClusterSet > get_cluster_set

(

)

Returns an object representing a ClusterSet.

Returns

The ClusterSet object to which the current session belongs to.

The returned object is identical to the one returned by create_cluster_set() and can be used to manage the ClusterSet.

The function will work regardless of whether the active session is established to an instance that belongs to a PRIMARY or a REPLICA Cluster, but its copy of the metadata is expected to be up-to-date.

This function will also work if the PRIMARY Cluster is unreachable or unavailable, although ClusterSet change operations will not be possible, except for failover with force_primary_cluster().

get_replica_set()

std::shared_ptr< ReplicaSet > get_replica_set

(

)

Returns an object representing a ReplicaSet.

The returned object is identical to the one returned by create_replica_set() and can be used to manage the replicaset.

The function will work regardless of whether the target instance is a PRIMARY or a SECONDARY, but its copy of the metadata is expected to be up-to-date. This function will also work if the PRIMARY is unreachable or unavailable, although replicaset change operations will not be possible, except for force_primary_instance().

kill_sandbox_instance()

None kill_sandbox_instance	(	int	port,
		dict	options
	)

Kills a running MySQL Server instance on localhost.

Parameters

port	The port of the instance to be killed.
options	Optional dictionary with options affecting the result.

Returns

Nothing.

This function will kill the process of a running MySQL Server instance on the local host. The following options affect the result:

• sandboxDir: path where the instance is located.

The sandboxDir must be the one where the MySQL instance was deployed. If not specified it will use:

~/mysql-sandboxes on Unix-like systems or %userprofile%\MySQL\mysql-sandboxes on Windows systems.

If the instance is not located on the used path an error will occur.

reboot_cluster_from_complete_outage()

Cluster reboot_cluster_from_complete_outage	(	str	clusterName,
		dict	options
	)

Brings a cluster back ONLINE when all members are OFFLINE.

Parameters

clusterName	Optional The name of the cluster to be rebooted.
options	Optional dictionary with options that modify the behavior of this function.

Returns

The rebooted cluster object.

The options dictionary can contain the next values:

• force: boolean value to indicate that the operation must be executed even if some members of the Cluster cannot be reached, or the primary instance selected has a diverging or lower GTID_SET.
• dryRun: boolean value that if true, all validations and steps of the command are executed, but no changes are actually made. An exception will be thrown when finished.
• primary: Instance definition representing the instance that must be selected as the primary.
• switchCommunicationStack: The Group Replication communication stack to be used by the Cluster after the reboot.
• ipAllowlist: The list of hosts allowed to connect to the instance for Group Replication traffic when using the 'XCOM' communication stack.
• localAddress: string value with the Group Replication local address to be used instead of the automatically generated one when using the 'XCOM' communication stack.
• timeout: integer value with the maximum number of seconds to wait for pending transactions to be applied in each instance of the cluster (default value is retrieved from the 'dba.gtidWaitTimeout' shell option).
• paxosSingleLeader: boolean value used to enable/disable the Group Communication engine to operate with a single consensus leader.

The value for switchCommunicationStack is used to choose which Group Replication communication stack must be used in the Cluster after the reboot is complete. It's used to set the value of the Group Replication system variable 'group_replication_communication_stack'.

When set to legacy 'XCom', all internal GCS network traffic (PAXOS and communication infrastructure) flows through a separate network address: the localAddress.

When set to 'MySQL', such traffic re-uses the existing MySQL Server facilities to establish connections among Cluster members. It allows a simpler and safer setup as it obsoletes the usage of IP allowlists (ipAllowlist), removes the explicit need to have a separate network address (localAddress), and introduces user-based authentication.

The option is used to switch the communication stack previously in use by the Cluster, to another one. Setting the same communication stack results in no changes.

The ipAllowlist format is a comma separated list of IP addresses or subnet CIDR notation, for example: 192.168.1.0/24,10.0.0.1. By default the value is set to AUTOMATIC, allowing addresses from the instance private network to be automatically set for the allowlist.

The value for localAddress is used to set the Group Replication system variable 'group_replication_local_address'. The localAddress option accepts values in the format: 'host:port' or 'host:' or ':port'. If the specified value does not include a colon (:) and it is numeric, then it is assumed to be the port, otherwise it is considered to be the host. When the host is not specified, the default value is the value of the system variable 'report_host' if defined (i.e., not 'NULL'), otherwise it is the hostname value. When the port is not specified, the default value is the port of the target instance if the communication stack in use by the Cluster is 'MYSQL', otherwise, port * 10 + 1 when the communication stack is 'XCOM'. In case the automatically determined default port value is invalid (> 65535) then an error is thrown.

The value for paxosSingleLeader is used to enable or disable the Group Communication engine to operate with a single consensus leader when the Cluster is in single-primary more. When enabled, the Cluster uses a single leader to drive consensus which improves performance and resilience in single-primary mode, particularly when some of the Cluster's members are unreachable.

The option is available on MySQL 8.0.31 or newer and the default value is 'OFF'.

The option is used to switch the value of paxosSingleLeader previously in use by the Cluster, to either enable or disable it.

This function reboots a cluster from complete outage. It obtains the Cluster information from the instance MySQL Shell is connected to and uses the most up-to-date instance in regards to transactions as new seed instance to recover the cluster. The remaining Cluster members are automatically rejoined.

On success, the restored cluster object is returned by the function.

The current session must be connected to a former instance of the cluster.

If name is not specified, the default cluster will be returned.

start_sandbox_instance()

None start_sandbox_instance	(	int	port,
		dict	options
	)

Starts an existing MySQL Server instance on localhost.

Parameters

port	The port where the instance listens for MySQL connections.
options	Optional dictionary with options affecting the result.

Returns

Nothing.

This function will start an existing MySQL Server instance on the local host. The following options affect the result:

• sandboxDir: path where the instance is located.

The sandboxDir must be the one where the MySQL instance was deployed. If not specified it will use:

~/mysql-sandboxes on Unix-like systems or %userprofile%\MySQL\mysql-sandboxes on Windows systems.

If the instance is not located on the used path an error will occur.

stop_sandbox_instance()

None stop_sandbox_instance	(	int	port,
		dict	options
	)

Stops a running MySQL Server instance on localhost.

Parameters

port	The port of the instance to be stopped.
options	Optional dictionary with options affecting the result.

Returns

Nothing.

This function will gracefully stop a running MySQL Server instance on the local host. The following options affect the result:

• sandboxDir: path where the instance is located.
• password: password for the MySQL root user on the instance.

The sandboxDir must be the one where the MySQL instance was deployed. If not specified it will use:

~/mysql-sandboxes on Unix-like systems or %userprofile%\MySQL\mysql-sandboxes on Windows systems.

If the instance is not located on the used path an error will occur.

upgrade_metadata()

None upgrade_metadata

(

dict

options

)

Upgrades (or restores) the metadata to the version supported by the Shell.

Parameters

options

Optional dictionary with option for the operation.

This function will compare the version of the installed metadata schema with the version of the metadata schema supported by this Shell. If the installed metadata version is lower, an upgrade process will be started.

The options dictionary accepts the following attributes:

• dryRun: boolean, if true all validations and steps to run the upgrade process are executed but no changes are actually made.

The Upgrade Process

When upgrading the metadata schema of clusters deployed by Shell versions before 8.0.19, a rolling upgrade of existing MySQL Router instances is required. This process allows minimizing disruption to applications during the upgrade.

The rolling upgrade process must be performed in the following order:

1. Execute dba.upgrade_metadata() using the latest Shell version. The upgrade function will stop if outdated Router instances are detected, at which point you can stop the upgrade to resume later.
2. Upgrade MySQL Router to the latest version (same version number as the Shell)
3. Continue or re-execute dba.upgrade_metadata()

Failed Upgrades

If the installed metadata is not available because a previous call to this function ended unexpectedly, this function will restore the metadata to the state it was before the failed upgrade operation.

Member Data Documentation

verbose

int verbose

Controls debug message verbosity for sandbox related dba operations.

The assigned value can be either boolean or integer, the result depends on the assigned value:

• 0: disables mysqlprovision verbosity
• 1: enables mysqlprovision verbosity
• >1: enables mysqlprovision debug verbosity
• Boolean: equivalent to assign either 0 or 1

session

Session session

The session the dba object will use by default.

Reference to the MySQL session that will be used as the default target for AdminAPI operations such as get_cluster() or create_cluster().

This is a read-only property.