Arcion CDC Agent

Real-time replication from SQL Server with Arcion CDC Agent #

For real-time replicaiton from SQL Server, you can choose Arcion CDC Agent as a CDC Extractor. Follow these steps to set up real-time replication using the Arcion CDC Agent.

I. Prerequisites #

Required permissions #

To allow replication, you need to first verify that the necessary permissions are in place on source SQL Server. For more information, see SQL Server User Permissions.

Primary keys on tables #

For full mode replication with Arcion CDC Agent, we recommend that all the tables that you need to replicate have primary keys. If it’s not possible to define primary key on a table, follow the instructions in Replicate tables without primary keys.

Set up Arcion CDC Agent #

To set up Arcion CDC Agent, follow the instructions in Arcion CDC Agent.

II. Set up connection configuration #

Specify the connection details of your SQL Server instance to Replicant in one of the following ways:

Use a connection configuration file #

The connection configuration fild holds the connection details and login credentials. You can find a sample connection configuration file sqlserver.yaml in the $REPLICANT_HOME/conf/conn directory. The following configuration parameters are available:

type #

The connection type representing the database. In this case, it’s SQLSERVER.

host #

The hostname of your SQL Server system.

port #

The port number to connect to the host.

username #

The username credential to access the SQL Server system.

password #

The password associated with username.

auth-type #

The authentication protocol for the connection. The following protocols are supported:

  • NATIVE (Default)
  • NLTM

Default authentication protocol is always NATIVE if you don’t explicitly set the auth-type parameter.

In case of NLTM protocol, provide the username in DOMAIN\USER format—for example, domain\alex.

extractor #

The CDC Extractor to use for real-time replication.

To use Arcion CDC Agent, follow these steps:

  1. Set extractor to LOG.
  2. Follow the instructions in Arcion CDC Agent Installation.

is_azure #

Optional parameter. If you’re hosting SQL Server on Azure, you must set this parameter to true.

max-connections #

The maximum number of connections Replicant uses to load data into the SQL Server system.

The following is a sample connection configuration:


host: localhost
port: 1433

username: 'USERNAME'
password: 'PASSWORD'

extractor: LOG


Configuration user for Arcion CDC Agent #

Arcion CDC Agent requires the sysadmin role to configure datbase publications and subscriptions that the Agent uses for replication. Therefore, Arcion supports new parameters in the SQL Server connection configuration file from version

config-username: 'sa'
config-password: 'Rocket0128'
config-auth-type: NATIVE

The three parameters in the preceding sample describe a configuration user. Arcion CDC Agent uses this configuration user to set up replication. You can specify these parameters either in plain text or in a KeyStore.

If you specify config-username, Arcion CDC Agent uses this user to set up replication. If you don’t specify config-username, Arcion CDC Agent uses the main username.

We recommend that you explicitly specify these three parameters if you’re using version and later.

Use a secrets management service #

You can store your connection credentials in a secrets management service and tell Replicant to retrieve the credentials. For more information, see Secrets management.

Use KeyStore for credentials #

Replicant supports consuming login credentials from a credentials store. Instead of specifying username and password in plain text, you can keep credentials in a KeyStore and provide the KeyStore details in the connection configuration file:

  type: {PKCS12|JKS|JCEKS}

Replace the following:

  • PATH_TO_KEYSTORE_FILE: The path to your KeyStore file.
  • PREFIX_OF_THE_KEYSTORE_ENTRY: The prefix of your KeyStore entries. You can create entries in the credential store using a prefix that preceeds each credential alias. For example, you can create KeyStore entries with aliases sqlserver_username and sqlserver_password. Therefore, you need to set key-prefix to sqlserver_.
  • KEYSTORE_PASSWORD: Optional parameter for the KeyStore password. If you don’t want to specify the KeyStore password here, then you must use the UUID from your license file as the KeyStore password. Keep your license file somewhere safe to keep the KeyStore password secure.

Note that the following parameters must have entries in the KeyStore:

Parameters for connection between Arcion CDC Agent and Replicant

  • sql-proxy-connection
  • agent-connection
  • sql-jobs-username
  • sql-jobs-password

Parameters for configuration user

  • config-username
  • config-password
KeyStore entries for usernames and passwords of the preceding parameters follow this structure:
<key-prefix> + “sql-proxy-connection-”
<key-prefix> + “agent-connection-”
<key-prefix> + “sql-jobs-”

For example, consider the following KeyStore configuration:

  type: PKCS12
  path: /data/store/sqlserver.jks
  key-prefix: "ss_"
  password: test01 

For the preceding configuration, you need to add KeyStore entries in the following manner:

Username and password of SQL Server

echo "sa" | keytool -importpass -keystore /data/store/sqlserver.jks -storetype pkcs12 -storepass test01 -alias ss_username -keypass test01 -noprompt
echo "Rocket0128" | keytool -importpass -keystore /data/store/sqlserver.jks -storetype pkcs12 -storepass test01 -alias ss_password -keypass test01 -noprompt

sql-jobs-username and sql-jobs-password

echo "TEST\administrator" | keytool -importpass -keystore /data/store/sqlserver.jks -storetype pkcs12 -storepass test01 -alias ss_sql-jobs-username -keypass test01 -noprompt
echo "Rocket0128" | keytool -importpass -keystore /data/store/sqlserver.jks -storetype pkcs12 -storepass test01 -alias ss_sql-jobs-password -keypass test01 -noprompt

Username and password of sql-proxy-connection

echo "sa" | keytool -importpass -keystore /data/store/sqlserver.jks -storetype pkcs12 -storepass test01 -alias ss_sql-proxy-connection-username -keypass test01 -noprompt
echo "Rocket0128" | keytool -importpass -keystore /data/store/sqlserver.jks -storetype pkcs12 -storepass test01 -alias ss_sql-proxy-connection-password -keypass test01 -noprompt

Username and password of agent-connection username and password

echo "alexwin10\alex" | keytool -importpass -keystore /data/store/sqlserver.jks -storetype pkcs12 -storepass test01 -alias ss_agent-connection-username -keypass test01 -noprompt
echo "Rocket0128" | keytool -importpass -keystore /data/store/sqlserver.jks -storetype pkcs12 -storepass test01 -alias ss_agent-connection-password -keypass test01 -noprompt

Username and password of configuration user

echo "sa" | keytool -importpass -keystore /data/store/sqlserver.jks -storetype pkcs12 -storepass test01 -alias ss_config-username -keypass test01 -noprompt
echo "Rocket0128" | keytool -importpass -keystore /data/store/sqlserver.jks -storetype pkcs12 -storepass test01 -alias ss_config-password -keypass test01 -noprompt

III. Create the heartbeat table #

For full mode replication, you need to create a heartbeat table. For example:

CREATE TABLE "tpcc"."dbo"."replicate_io_cdc_heartbeat"("timestamp" BIGINT NOT NULL, PRIMARY KEY("timestamp"))

IV. Set up Extractor configuration #

To configure real-time replication according to your requirements, specify your configuration in the Extractor configuration file. You can find a sample sqlserver.yaml in the $REPLICANT_HOME/conf/src directory.

All configuration parameters for realtime mode live under the realtime section. The following is a sample configuration:

  threads: 4
  fetch-size-rows: 10000
  fetch-duration-per-extractor-slot-s: 3
    enable: true
    catalog: "tpcc"
    schema: "dbo"
    interval-ms: 10000

For more information about the configuration parameters in realtime mode, see Realtime Mode.

Replicate tables without primary keys #

To use Arcion CDC Agent as CDC Extractor, we recommend that all replicated tables have primary keys. However, it’s possible to replicate tables without primary keys if the tables meet the following criteria:

The tables must have a set of non-nullable columns that uniquely identifies each row.

Replicant replicates a table without a primary key by creating a view of that table and then replicating that view instead. By default, each view Replicant creates has the following two properties:

  • Each view belongs to the dbo schema.
  • The name of each view starts with the prefix replicant_.

However, you can change these default properties by specifying the following respective parameters in the SQL Server source connection configuration file:

auxiliary-object-schema #

The name of the schema to which the view belongs to.

auxiliary-object-prefix #

The prefix to use for the name of each view.

For example, the following connection configuration for SQL Server uses the preceding parameters to set the view properties:


host: localhost
port: 1433

username: 'alex'
password: 'alex1995'

extractor: LOG

max-connections: 30

auxiliary-object-schema: 'admin'
auxiliary-object-prefix: 'price_'