The Challenge
Business Problem
Teams write disaster recovery plans but never test them. When a real outage hits, the failover process has bitrotted and doesn't work as expected.
The Approach
Solution Overview
Connect PostgreSQL, AWS, and Slack MCP Servers to periodically test failover to secondary databases, verify data consistency, and report results.
Step-by-Step
Implementation Steps
1
Schedule Failover Tests
Set up regular (monthly) automated failover tests during low-traffic windows.
2
Execute Failover
Switch traffic to the secondary database region and verify all services continue working.
3
Validate Data
Run data consistency checks between primary and secondary after failover.
async function testFailover() {
await slack.sendMessage({ channel: '#ops', text: '🔄 Starting scheduled failover test...' });
const primaryCount = await postgres.query('SELECT count(*) FROM critical_table', [], { host: PRIMARY });
await aws.updateDNS({ recordName: 'db.internal', value: SECONDARY_HOST });
await sleep(30000);
const secondaryCount = await postgres.query('SELECT count(*) FROM critical_table', [], { host: SECONDARY });
const consistent = primaryCount === secondaryCount;
await slack.sendMessage({ channel: '#ops', text: `Failover test ${consistent ? '✅ PASSED' : '❌ FAILED'}: Primary=${primaryCount}, Secondary=${secondaryCount}` });
// Failback
await aws.updateDNS({ recordName: 'db.internal', value: PRIMARY_HOST });
}4
Report and Alert
Generate failover test reports and alert if any tests fail.
Code
Code Examples
typescript
Consistency Checker
async function checkConsistency(tables) {
const results = [];
for (const table of tables) {
const primary = await postgres.query(`SELECT count(*), max(updated_at) FROM ${table}`, [], { host: PRIMARY });
const secondary = await postgres.query(`SELECT count(*), max(updated_at) FROM ${table}`, [], { host: SECONDARY });
results.push({ table, consistent: primary.count === secondary.count, lag: primary.max - secondary.max });
}
return results;
}Overview
ComplexityHard
Estimated Time~16 hours
Tools Used
PostgreSQL MCP ServerAWS MCP ServerSlack MCP Server
Industry
TechnologyFinanceHealthcare
ROI Metrics
Time Saved8 hours per test cycle
Cost ReductionProven DR readiness
Efficiency GainMonthly automated validation