Issue
The system was reported as hanging and running slowly for a period of time. Users experienced slow response, including door unlock commands taking around 30 seconds to respond. The condition self-recovered without intervention and the system remained stable afterward.
Product Line
EcoStruxure Security Expert
Environment
- Security Expert Client Server
- Microsoft SQL Server
Cause
Analysis of the SQL Server Application Log, SQL ERRORLOG, and Windows System Log identified multiple storage-related warnings during the reported outage window. The following events were recorded during the period when users experienced system hangs and slow response times:
| Event |
|---|
| SQL Event 833 - Long I/O detected on SecurityExpert transaction log file (SecurityExpert.ldf) |
| SQL Event 833 - Long I/O detected on SecurityExpertEvents database file (SecurityExpertEvents.mdf) |
| SQL Event 833 - Long I/O detected on SecurityExpert database file (SecurityExpert.mdf) |
| SQL Event 833 - Long I/O detected on SecurityExpertEvents transaction log file (SecurityExpertEvents.ldf) |
| SQL Event 833 - Long I/O detected on SecurityExpertEvents database file (SecurityExpertEvents.mdf) |
| ESENT Event 508 - Storage latency warning |
These events indicated that database and transaction log I/O requests for the SecurityExpert and SecurityExpertEvents databases were taking up to 30 seconds to complete. The ESENT Event 508 warning further showed that the latency was observable outside SQL Server and also affected the Windows ESENT subsystem.
Review of historical SQL ERRORLOG files showed similar long-I/O warnings occurring repeatedly over several weeks. Based on the available log evidence, underlying storage latency was identified as the most probable cause of the application slowdown and system hang behavior.
Resolution
Review of the SQL Server Application Log, SQL ERRORLOG files, and Windows System Log confirmed that SQL Server remained online throughout the incident and did not experience a service crash, restart, database recovery, or corruption event. Long I/O warnings affecting the SecurityExpert and SecurityExpertEvents databases were identified during the outage window. Historical review of the SQL ERRORLOG showed similar long-I/O warnings occurring repeatedly over several weeks, indicating an ongoing storage performance issue rather than an isolated application fault. The findings were provided for further investigation of the SQL Server infrastructure and storage performance.
