How to fix ERROR 1598: Binary logging not possible in MySQL

Connect to MySQL and verify the current settings:

SHOW GLOBAL VARIABLES LIKE 'binlog_format';
SHOW GLOBAL VARIABLES LIKE 'transaction_isolation';

This will show you if there's a conflict. If you see STATEMENT format with READ-COMMITTED or READ-UNCOMMITTED isolation, that's the problem.

For persistent changes, edit your MySQL configuration file (/etc/mysql/my.cnf or /etc/my.cnf):

[mysqld]
binlog_format = ROW

Then restart MySQL:

sudo systemctl restart mysql
# or on systems using mysqld_safe:
sudo mysqld_safe

ROW-based logging is safer for replication with all isolation levels. It logs the actual row changes rather than the SQL statement, preventing consistency issues.

If you need to change immediately without restarting (for new connections only):

SET GLOBAL binlog_format = 'ROW';

If you prefer automatic format switching, MIXED mode uses statement-based logging by default but switches to row-based for unsafe statements:

[mysqld]
binlog_format = MIXED

Then restart MySQL. MIXED format provides a good balance but may cause larger binary logs than pure ROW format.

If you're using a READ-COMMITTED or READ-UNCOMMITTED isolation level, consider changing to REPEATABLE-READ:

SET GLOBAL transaction_isolation = 'REPEATABLE-READ';

This setting takes effect for new connections. Existing connections retain their previous isolation level.

If you still see the error after configuration changes, verify the MySQL daemon can write to the datadir:

# Find the datadir location
mysql -u root -p -e "SHOW VARIABLES LIKE 'datadir';"

# Check ownership and permissions (replace /var/lib/mysql with your datadir)
ls -ld /var/lib/mysql
ls -la /var/lib/mysql/mysql-bin.*

# Fix ownership if needed (MySQL 8.0+)
sudo chown -R mysql:mysql /var/lib/mysql
sudo chmod 750 /var/lib/mysql

In Docker/Kubernetes environments, ensure the volume is mounted with mysql (uid 999 or similar) ownership:

docker run -d \
  -v /path/to/volume:/var/lib/mysql \
  mysql:latest

If the binary log cannot be created at startup, verify free disk space:

df -h /var/lib/mysql

# If full, rotate existing logs to free space
mysql -u root -p -e "PURGE BINARY LOGS BEFORE DATE_SUB(NOW(), INTERVAL 3 DAY);"

# Or disable binary logging if recovery/replication isn't needed
# Add to my.cnf:
# skip-log-bin
# Then restart MySQL

Always test your configuration file syntax before restarting:

mysqld --validate-config

This catches syntax errors and prevents startup failures. Look for "mysqld: ready for connections" in the output.