/amazon-aurora-postgresql

Pre-Upgrade Checklist

Common Steps (Both Engines)

1. Create test environment via snapshot restore

   aws rds create-db-cluster-snapshot --db-cluster-identifier {cluster} \
     --db-cluster-snapshot-identifier {cluster}-pre-upgrade-snapshot --region {region}
   aws rds restore-db-cluster-from-snapshot --db-cluster-identifier {cluster}-upgrade-test \
     --snapshot-identifier {cluster}-pre-upgrade-snapshot \
     --engine {engine} --engine-version {target_version} --region {region}

2. Review and create new parameter group

   aws rds describe-db-cluster-parameters --db-cluster-parameter-group-name {current_pg} \
     --query "Parameters[?Source=='user' && ParameterValue!=null].{Name:ParameterName,Value:ParameterValue}" \
     --output table --region {region}

   Create new group for target version family and apply custom parameters.

3. Check pending maintenance actions

   aws rds describe-pending-maintenance-actions \
     --resource-identifier arn:aws:rds:{region}:{account}:cluster:{cluster} --region {region}

4. Capture baseline performance metrics — CloudWatch: CPUUtilization, DatabaseConnections, ReadLatency, WriteLatency, FreeableMemory, BufferCacheHitRatio. Save EXPLAIN plans for critical queries.

5. Consider Blue/Green Deployments for minimal downtime. Ref: https://docs.aws.amazon.com/AmazonRDS/latest/AuroraUserGuide/blue-green-deployments.html

6. Plan maintenance window — schedule during lowest traffic (use Performance Insights).

Aurora PostgreSQL-Specific

1. Check extension compatibility with target version.

2. Review PostgreSQL release notes for each major version between current and target:

   • PG 14: https://www.postgresql.org/docs/14/release-14.html
   • PG 15: https://www.postgresql.org/docs/15/release-15.html
   • PG 16: https://www.postgresql.org/docs/16/release-16.html
   • PG 17: https://www.postgresql.org/docs/17/release-17.html

3. Check encoding/locale compatibility with target.

4. Test on snapshot-restored cluster — Aurora handles pg_upgrade internally.

5. Check objects owned by rdsadmin — can block upgrades.

6. Drop unused logical replication slots — active slots block major upgrades.