/**
* MySQL Prompt - Replication Setup
*
* MySQL replication configuration guide.
*/
import type { PromptDefinition, RequestContext } from '../../../types/index.js';
export function createSetupReplicationPrompt(): PromptDefinition {
return {
name: 'mysql_setup_replication',
description: 'MySQL replication setup and configuration guide',
arguments: [
{ name: 'type', description: 'Replication type: async, semisync, group', required: false }
],
handler: (args: Record<string, string>, _context: RequestContext) => {
const replicationType = args['type'] ?? 'async';
return Promise.resolve(`# MySQL Replication Setup Guide
Configure MySQL replication for high availability and read scaling.
**Replication Type:** ${replicationType}
## Step 1: Check Current Replication Status
Use \`mysql://replication\` resource to check:
- Current role (source/replica/standalone)
- Binary log configuration
- GTID status
## Step 2: Prepare Source Server
### Enable Binary Logging
\`\`\`ini
# my.cnf on source
[mysqld]
server-id = 1
log_bin = mysql-bin
binlog_format = ROW
gtid_mode = ON
enforce_gtid_consistency = ON
\`\`\`
### Create Replication User
\`\`\`sql
CREATE USER 'repl'@'%' IDENTIFIED BY 'replication_password';
GRANT REPLICATION SLAVE ON *.* TO 'repl'@'%';
\`\`\`
## Step 3: Prepare Replica Server
### Configure Replica
\`\`\`ini
# my.cnf on replica
[mysqld]
server-id = 2
log_bin = mysql-bin
relay_log = relay-bin
gtid_mode = ON
enforce_gtid_consistency = ON
read_only = ON
super_read_only = ON
${replicationType === 'semisync' ? `
# Semi-synchronous replication
rpl_semi_sync_replica_enabled = 1` : ''}
\`\`\`
## Step 4: Initialize Replica
### Option A: GTID-based (Recommended)
\`\`\`sql
CHANGE REPLICATION SOURCE TO
SOURCE_HOST = 'source-host',
SOURCE_PORT = 3306,
SOURCE_USER = 'repl',
SOURCE_PASSWORD = 'replication_password',
SOURCE_AUTO_POSITION = 1;
START REPLICA;
\`\`\`
### Option B: Binary Log Position
\`\`\`sql
-- Get position from source
SHOW BINARY LOG STATUS;
-- On replica
CHANGE REPLICATION SOURCE TO
SOURCE_HOST = 'source-host',
SOURCE_PORT = 3306,
SOURCE_USER = 'repl',
SOURCE_PASSWORD = 'replication_password',
SOURCE_LOG_FILE = 'mysql-bin.000001',
SOURCE_LOG_POS = 123456;
START REPLICA;
\`\`\`
## Step 5: Verify Replication
Use these tools to verify:
- \`mysql_replication_status\` - Detailed status
- \`mysql_replication_lag\` - Check replication delay
- \`mysql://replication\` - Overall status
\`\`\`sql
SHOW REPLICA STATUS\\G
\`\`\`
Key things to check:
- Replica_IO_Running: Yes
- Replica_SQL_Running: Yes
- Seconds_Behind_Source: 0 (or low)
## Semi-Synchronous Replication
For reduced data loss risk:
\`\`\`sql
-- On source
INSTALL PLUGIN rpl_semi_sync_source SONAME 'semisync_source.so';
SET GLOBAL rpl_semi_sync_source_enabled = 1;
-- On replica
INSTALL PLUGIN rpl_semi_sync_replica SONAME 'semisync_replica.so';
SET GLOBAL rpl_semi_sync_replica_enabled = 1;
\`\`\`
## Monitoring
Regular monitoring should include:
- Replication lag trends
- Binary log volume
- Error log for replication errors
- GTID gaps
## Failover Procedure
1. Verify replica is caught up
2. Stop replication on replica
3. Promote replica: \`SET GLOBAL read_only = OFF;\`
4. Update application connection strings
5. Re-point other replicas to new source
Start by checking current replication status with \`mysql://replication\`.`);
}
};
}
