+++
title = "Configure Source Database"
weight = 25
+++
### Run DMS Replication Task with Change Data Capture (CDC)
To ensure minimal downtime for the database migration, we're going to use continuous replication of changes (also known as **Change Data Capture (CDC)**) from the source database to the target database. For more information about CDC and native CDC support of **AWS DMS** see this article.
#### Enable binary log on the source database
For **AWS DMS** continuous replication from MySQL database, you'll need to enable the binary log and make configuration changes on the source database.
1. Login to the **Source Environment Database** server
For **self-paced lab** - information needed to access the Database environment is described in the **Output** section of the **ApplicationMigrationWorkshop** CloudFormation Template.
For **AWS Event** - information needed to access the Database environment is described at **Database IP**, **Database Username** and **Database SSH Key** on the Team Dashboard.
If you're not sure how to use SSH to access servers, check the following:
- For Microsoft Windows users view this article.
- For Mac OS users view this article.
2. Grant additional privileges to the **wordpress-user** database user
Run the following commands on the database server:
```
sudo mysql -u root -pAWSRocksSince2006
GRANT REPLICATION CLIENT ON *.* to 'wordpress-user';
GRANT REPLICATION SLAVE ON *.* to 'wordpress-user';
GRANT SUPER ON *.* to 'wordpress-user';
exit
```
3. Create a folder for the **bin logs**
Run the following commands on the database server:
```
sudo su -
mkdir /var/lib/mysql/binlogs
chown -R mysql:mysql /var/lib/mysql/binlogs
exit
```
More information on the binary log can be found in the MySQL documentation.
4. Create and modify **/etc/mysql/my.cnf** file
Run the following to edit the file:
```
sudo su -
cp /etc/mysql/mysql.conf.d/mysqld.cnf /etc/mysql/my.cnf
chown -R mysql:mysql /etc/mysql/my.cnf
nano /etc/mysql/my.cnf
```
Then add the following information under the **[mysqld]** section, save the file and exit nano:
```
server_id=1
log-bin=/var/lib/mysql/binlogs/log
binlog_format=ROW
expire_logs_days=1
binlog_checksum=NONE
binlog_row_image=FULL
log_slave_updates=TRUE
performance_schema=ON
```
5. **Restart** MySQL service to apply changes
Back in the console, run the following command to apply the changes:
```
sudo service mysql restart
```
{{% notice warning %}}
Applying those changes requires mysql service restart. This will interrupt the source database for a few seconds.
{{% /notice %}}
1. **Test** the changes
Make sure the update in **/etc/mysql/my.cnf** took effect, by running the following commands:
```
sudo mysql -u root -pAWSRocksSince2006
select variable_value as "BINARY LOGGING STATUS (log-bin) :: "
from performance_schema.global_variables where variable_name='log_bin';
select variable_value as "BINARY LOG FORMAT (binlog_format) :: "
from performance_schema.global_variables where variable_name='binlog_format';
exit
```
The output must show the **BINARY LOGGIN STATUS** set to **ON**, as on the screenshot below:
If that's the case - you can **exit** from the SSH, in case of problems - check the **/var/log/mysqld.log** file for errors.