Today I Learned — Daily learnings
Running create-blue-green-deployment with the default parameter group fails with SourceClusterNotSupportedFault. Set rds.logical_replication = 1 for PostgreSQL or binlog_format = ROW for MySQL, then reboot all instances.
aws-advanced-jdbc-wrapper 2.6.4 brings in slf4j-api 1.7.36 as a transitive dependency, conflicting with HikariCP 6.x which requires SLF4J 2.x. Exclude 1.7 and explicitly declare slf4j-api 2.0.
All connections are dropped during Blue/Green Switchover, but HikariCP may reconnect to the old writer via DNS cache. Write queries fail with read-only transaction errors. Same behavior on both PostgreSQL and MySQL.
Setting us-east-1 in aws-targets.json doesn't help if AWS_REGION is set to ap-northeast-1. CDK under the hood picks up the env var. Not documented in CLI docs.
agentcore deploy fails with Unrecognized resource types: [AWS::BedrockAgentCore::Evaluator] in ap-northeast-1. Switch to us-east-1.
agentcore deploy fails with CloudFormation ROLLBACK if the Gateway target MCP server is unreachable. Error: Failed to connect and fetch tools from the provided MCP target server.
agentcore remove all --force only resets local config files. AWS resources remain until you run agentcore deploy to apply the empty state.
agentcore invoke --session-id with a short string fails with Member must have length greater than or equal to 33. Use UUIDs or long identifiers.
Strands SDK A2A server sets the card url to http://0.0.0.0:9000/ by default. Fix by setting a2a.http_url to the Kubernetes Service FQDN in Helm values.
After fixing an A2A URL, the agent kept using the old one. Stale tool call results in S3 session history were restored into the LLM context. Fixed by clearing sessions.