How to fix ERROR 1296: Got error from NDBCLUSTER in MySQL

The error message includes a code like 157, 4009, 4350, etc. Run the failing query and note the exact error code. This determines your next step:

SELECT * FROM your_table WHERE condition;
-- Check the error message format: ERROR 1296 (HY000): Got error [NDB_CODE] ...

Use the NDB management tool to check if all cluster nodes are running:

ndb_mgm -e "show"

Expected output shows all data nodes as "Started" and all API nodes as "Bin log" or "API". If nodes show "Stopped" or "Unknown", the cluster is down and needs to be restarted.

Verify the MySQL server can communicate with the cluster:

SHOW ENGINE NDB STATUS\G

If this query fails or shows "disconnected", the mysqld process cannot reach the cluster nodes. Check firewall rules and ndb_connectstring configuration:

# In /etc/mysql/my.cnf
[mysqld]
ndb_connectstring=management_host:1186

If the cluster is down, restart it in order (management node first, then data nodes, then MySQL servers):

# On management node:
ndb_mgm -e "shutdown"
sleep 2
ndb_mgmd -f /path/to/config.ini

# On each data node:
ndbd --ndb-connectstring=mgmt_host:1186

# Restart mysqld
sudo service mysql restart

This error typically occurs with duplicate keys in unique indexes or constraint violations. Adjust your INSERT/UPDATE logic:

```sql
-- Use INSERT IGNORE to skip duplicates (requires testing)
INSERT IGNORE INTO your_table (col1, col2) VALUES (val1, val2);

-- Or use ON DUPLICATE KEY UPDATE
INSERT INTO your_table (id, col1, col2) VALUES (1, 'a', 'b')
ON DUPLICATE KEY UPDATE col2 = 'b';

-- Or check constraints first
IF NOT EXISTS (SELECT 1 FROM your_table WHERE unique_col = value) THEN
INSERT INTO your_table (...) VALUES (...);
END IF;

Network issues or firewall rules may block cluster communication:

# Test connectivity from MySQL host to cluster nodes
nc -zv cluster_node_ip 3306
nc -zv cluster_node_ip 1186

# Check for packet loss
ping -c 4 cluster_node_ip

# Verify no iptables rules blocking cluster ports (1186, 3306, 2202)
sudo iptables -L -n | grep -E "1186|3306|2202"

Ensure all cluster nodes are on stable network connections.

If DataMemory or IndexMemory is exhausted:

# Edit cluster config.ini
sudo nano /path/to/config.ini

# Increase these values:
[ndbd]
DataMemory=4G      # Increase as needed
IndexMemory=1G     # Increase as needed
MaxNoOfAttributes=2000

Then perform a rolling restart of all data nodes (gradual to avoid downtime).

If running multiple SQL nodes, stored procedures must be manually created on each:

-- Connect to first SQL node and create procedure
CREATE PROCEDURE get_data()
BEGIN
  SELECT * FROM ndb_table;
END;

-- Connect to second SQL node and create the same procedure
CREATE PROCEDURE get_data()
BEGIN
  SELECT * FROM ndb_table;
END;

-- Repeat for all SQL nodes

Stored procedures are stored locally on each SQL node, not in the cluster itself.

For bulk inserts or updates that trigger error 1296:

-- Load in smaller chunks instead of all at once
LOAD DATA INFILE '/path/to/file.txt' INTO TABLE your_table
LIMIT 10000;  -- Process in batches

-- Or batch inserts in application code
for batch in chunks(data, size=1000):
    INSERT INTO your_table VALUES (batch)

This reduces cluster memory pressure and transaction size.