failures Archives

Tech Optimizer

July 30, 2026

Generating Referentially Consistent Synthetic Test Data for PostgreSQL in .NET Application Modernization

Satyajit Gokhale, Aiswaryaa Venugopalan, Ruchi Agarwal, Nits Jeganathan, Khurram Khawaja, Vijay Mandadi, and Luke Huan contributed to this article. AWS Transform offers a .NET application modernization service that allows enterprise customers to migrate from Microsoft SQL Server to Amazon Aurora PostgreSQL Compatible Edition. This migration reduces licensing costs and enhances scalability while utilizing an open-source ecosystem. Schema conversion tools can assist in translating DDL to PostgreSQL-compatible definitions, but correctness must be verified by teams to ensure performance under real-world workloads. Traditional testing methods, such as using production data or manual checks, are not scalable and raise privacy concerns. Therefore, there is a need for realistic synthetic data generated at scale that adheres to the migrated schema's constraints. AWS Transform for SQL Server modernization employs an AI agent to generate constraint-respecting synthetic data at scale during the migration workflow. This process involves loading the PostgreSQL schema into a live database, constructing a dependency graph for data generation, and distributing tasks across multiple sub-agents. The agent validates each generated INSERT against the live database, ensuring compliance with constraints and providing error diagnostics for any violations. The synthetic data generation workflow consists of four stages: schema analysis, establishing generation order, distributing tasks across sub-agents, and validation with error recovery. The agent extracts metadata from the PostgreSQL schema, determines a valid table generation sequence, parallelizes data generation while maintaining referential integrity, and generates and validates data row-by-row against the live database. Each successful insertion enriches the context for subsequent generations, while errors are handled through structured diagnostics and iterative regeneration. The process ensures referential integrity and preserves the generation state, allowing for recovery from interruptions without data loss.

Winsage

July 29, 2026

Missed Windows 11 Secure Boot? Don’t panic, Microsoft is still pushing it in the coming months

Microsoft reassured Windows 11 and Windows 10 users that their PCs will continue to boot normally and receive updates even if they have not yet received the new Secure Boot 2023 certificates. The rollout of these certificates is expected to continue over the upcoming months. The initial Secure Boot certificate expired on June 24, 2026, and Microsoft has been replacing older 2011 certificates since 2024. The latest update, KB5101650, transitioned Windows 11 to OS builds 26200.8875 and 26100.8875 for versions 25H2 and 24H2, respectively. The 2023 certificates replace older certificates with modern cryptographic standards, allowing Microsoft to deliver DBX revocation updates without interruption. Devices using the 2011 KEK can only receive DBX updates signed with that key, which is no longer valid after June 24. Microsoft has been rolling out the 2023 certificates for the past two years, and many devices remained in a yellow or red status by the June deadline. To check Secure Boot status, users can navigate to Windows Security > Device Security. A green checkmark indicates successful application of the certificates, while yellow and red alerts indicate compatibility issues or firmware incompatibility. PCs that are older or operating in Legacy BIOS mode will not receive the updates. Windows 10 also receives Secure Boot updates, but enrollment in Extended Security Updates (ESU) is required.

Tech Optimizer

July 28, 2026

‘PGSimCity’ shows how the PostgreSQL database actually works internally in a SimCity-like 3D environment.

PGSimCity is a web application that provides a 3D visualization of PostgreSQL's architecture, allowing users to explore its internal operations during SQL query execution. The application features an interactive interface that guides users through the connection process to PostgreSQL, illustrating how client connections reach the Postmaster and backend processes. It highlights the significance of connection pooling and the impact of increasing connections on backend processes. In the 'Query Lab' section, SQL statements are transformed into execution plans, showcasing processes like Parser, Rewriter, Planner, and Executor, along with execution paths such as Seq Scan and Index Scan. The shared_buffers area represents PostgreSQL's buffer cache, optimizing performance by reading data in 8KiB pages. Visualizations depict data pages stored on disk, with pathways showing the movement of pages to shared_buffers. The Write-Ahead Log (WAL) mechanism records changes for recovery, and transaction commits wait for WAL records to be flushed. Checkpointing writes dirty pages to storage in batches, which can cause latency spikes. PostgreSQL uses Multi-Version Concurrency Control (MVCC) to manage updated rows and dead tuples, which are cleaned up by autovacuum processes. The application also illustrates replication, where WAL from the primary server is sent to the standby server to maintain data consistency. Overall, PGSimCity provides a comprehensive view of PostgreSQL's components and potential performance issues related to caching, WAL management, checkpointing, vacuuming, and replication.

Winsage

July 24, 2026

Microsoft shares some details on Azure outage that blocked Windows 11 update downloads

This week, Meta experienced a global outage affecting Facebook users, followed by Microsoft facing performance issues with its M365 services, including Teams and SharePoint. Microsoft also reported difficulties with Azure, impacting Windows 11 updates and the Microsoft Store. The issues began around 11:15 AM PST on July 23, 2026, with a notification to users about the Azure outage affecting Windows Update and related services. Microsoft initiated recovery efforts and by 1:45 PM PST, announced that the issues were resolved and services were restored. Currently, there are no ongoing issues reported on the Microsoft Service Health Status page, but the incident is documented on the Windows Release Health page.

Tech Optimizer

July 24, 2026

How we pushed CDC into Postgres, and turned replication into clockwork

Making data from transactional databases accessible to analytical databases is essential in modern data architecture, but it faces challenges such as fragile tooling, high costs, and complex operations. Snowflake has developed a Postgres service that addresses these issues by reimagining Postgres replication. Postgres is a strong operational database, but its change data capture (CDC) capabilities need improvement. Many data pipelines are fragile due to complexities in managing continuous data flow, schema changes, snapshots, and failures. To enhance user experience with Snowflake Postgres, a complete reinvention of the replication process was necessary. A new feature called data mirroring is in public preview, allowing resilient data replication into Snowflake with low cost, minimal lag, and transactional consistency. This feature directly pushes changes from Postgres into Apache Iceberg™ tables in transactional batches, which are then automatically applied to Snowflake tables without extra infrastructure. Change data capture records changes from a transactional database for replay on another system, primarily using logical decoding in Postgres. This method decodes WAL records into logical operations, but the client bears the responsibility for subsequent steps like backfilling, managing schema changes, and handling failures. Built-in logical replication in Postgres only addresses some complexities. A limitation of logical decoding is that the external system does not recognize the state of Postgres, making it difficult to detect schema changes or correlate snapshots with changes. The solution is to push changes from Postgres into a data lake, specifically into Iceberg tables using compressed Parquet format, with object stores like Amazon S3 as the destination. The mirroring process uses a new Postgres extension called snowflake_cdc, which continuously pushes batches of changes into per-table change logs and a meta log. This extension understands the Postgres environment, coordinating schema changes and complex transactions while ensuring alignment between snapshots and changes.

Tech Optimizer

July 21, 2026

I Built My Second ETL Pipeline. This Time, I Started Thinking Like a Data Engineer

The author transitioned from a data analyst role to a data engineer, creating a 12-month self-study roadmap focused on learning by building projects. The first project was a GitHub ETL pipeline, which evolved from a simple Python script to a more complex system using SQLite and GitHub Actions for automation. The author realized that the challenges of data engineering lay in system design and orchestration rather than just writing ETL logic. For the second project, the author built an automated RSS ingestion pipeline to explore engineering decisions in creating a reliable data pipeline. The project emphasized the importance of separating application responsibilities from orchestration tasks, leading to the use of Docker for consistent execution environments and Kestra for orchestration. The author validated each component of the project incrementally: first the Python ETL, then PostgreSQL, followed by Docker, and finally Kestra. This approach ensured that each layer functioned correctly before adding complexity. The final architecture included distinct responsibilities for each component: Python for data processing, PostgreSQL for data storage, Docker for execution, and Kestra for orchestration. The author learned that effective engineering involves considering system reliability, error handling, and observability, shifting the focus from merely writing code to designing entire systems. The experience transformed the author's mindset, emphasizing the importance of incremental building and the separation of execution and orchestration responsibilities.

Winsage

July 21, 2026

Microsoft Confirms WSUS Sync Issue Causing Update Delays and Timeouts

Microsoft has identified synchronization delays and timeout errors affecting Windows Server Update Services (WSUS), which risks the timely delivery of Windows updates. WSUS is a management tool for distributing Windows updates across networks. Microsoft deprecated WSUS in September 2024 but continues to provide security fixes and updates. The synchronization issue has led to failures and delays in downloading update metadata, particularly impacting Windows 11 version 23H2 and later, Windows 10 version 1607, and Windows Server 2012 and later. This issue began around July 13, 2026, with mitigation efforts starting on July 18, 2026. Microsoft has released a partial fix for newly installed or rebuilt WSUS servers, while existing servers may still face challenges. The company is developing additional fixes and guidance. In previous years, Microsoft dealt with other WSUS-related issues affecting enterprise clients.

AppWizard

July 21, 2026

Google’s latest Android 17 beta fixes Bluetooth headaches and Gemini crashes

Android 17 QPR2 Beta 1 has launched, initiating the testing phase for the Pixel Feature Drop set for December 2026. This beta aims to fix issues affecting Pixel users, including Bluetooth reconnection failures, media control glitches on the lock screen, unexpected reboots when launching the Gemini AI assistant, and touch input bugs. The update has the build number CP41.260701.005 and supports various Pixel devices, including the Pixel 6a, Pixel 7 series, Pixel Fold, Pixel Tablet, Pixel 8 series, Pixel 9 family, and Pixel 10 models. Users can access it via the Android Beta Program or Android Emulator. Owners of the Pixel 6 and 6 Pro will no longer receive beta updates as they have reached their update limits.

Winsage

July 20, 2026

Windows 11’s biggest updates may need multiple reboots, but that’s normal, don’t force shutdown

Users may experience double reboots when installing substantial Windows updates, such as the April and July 2026 Updates, due to factors like Secure Boot and .NET Framework updates. The July 2026 .NET Framework update specifically requires a separate reboot. Microsoft is still rolling out the Secure Boot 2023 certificate update, which may also lead to multiple reboots. Users are advised not to panic during these reboots and to allow the system time to complete the installation process. Additionally, Microsoft has warned against delaying updates for more than three days due to increasing update sizes related to security vulnerabilities. Some users may encounter SCEP certificate errors in the Event Viewer after the July 2026 Update, but these errors do not indicate a failure of the update process.

Winsage

July 20, 2026

July 2026 Patch Tuesday: KB5101650 Windows 11 Update

On July 14, 2026, Microsoft released cumulative update KB5101650 for Windows 11 versions 25H2 and 24H2, addressing OS Builds 26200.8875 and 26100.8875. This update includes essential security fixes, updates to Secure Boot certificates, and enhanced Remote Desktop Protocol (RDP) defenses against phishing attacks. It consolidates July 2026's security content, addressing known vulnerabilities and introducing functional improvements. The update is critical for minimizing exposure to identified threats and is prioritized for systems managing remote access or nearing certificate expiration. The update enhances Remote Desktop security by supporting SHA-2 certificate thumbprints while retaining SHA-1 for legacy compatibility. It includes new Group Policy options to mitigate phishing risks associated with malicious .rdp files. The curl upgrade to version 8.21.0 incorporates security patches for command-line tools in Windows environments. Secure Boot certificates are automatically updated through Windows updates, ensuring boot security across various hardware. KB5101650 installs primarily through the Windows Update interface, requiring a restart to activate changes. Enterprise environments can use the Microsoft Update Catalog for manual distribution. A temporary restriction affects certain Dell devices with Intel Innovation Platform Framework drivers, which Microsoft plans to address in a future update. The cumulative update resolves a total of 622 Microsoft CVEs, including 416 affecting Windows components. Users are advised to verify and install the update promptly to secure the full suite of improvements.