sqlerrorlog-review

SQL Server ERRORLOG Review Skill

Purpose

Parse and analyze SQL Server ERRORLOG content to surface operational warnings, high-availability failures, resource pressure signals, security events, and configuration anomalies. Applies 33 checks (E1–E33) across six categories:

• E1–E8 — AG / High Availability: failovers, lease expiry, replica state changes, synchronization errors
• E9–E14 — Memory and resource pressure: page allocation failures, OS paging, worker exhaustion, non-yielding schedulers
• E15–E19 — I/O and storage: slow I/O subsystem, corruption warnings, tempdb exhaustion, log backup gaps, VLF proliferation
• E20–E24 — Startup, shutdown, and connectivity: abnormal termination, restart cycling, login failure bursts, linked server errors
• E25–E28 — Configuration and informational: trace flags, unconfigured max memory, log rotation gaps, version end-of-support
• E29–E33 — SQL 2019/2022 modern features: ADR PVS cleanup stall, IQP DOP feedback, Ledger verification failure, CE feedback model change, Azure Arc agent disconnect

Input

Accept any of:

• File path — path to the SQL Server ERRORLOG file (default location: C:\Program Files\Microsoft SQL Server\MSSQL<ver>.<inst>\MSSQL\Log\ERRORLOG)
• Inline paste — raw ERRORLOG text pasted directly into chat; partial excerpts are valid
• Natural language description — describe the symptoms or paste selected log lines with context

For best results, provide the current ERRORLOG and at least one prior log (ERRORLOG.1). When only partial content is available, state which time range is covered.

Capture via T-SQL

-- Read current ERRORLOG (0 = current, 1 = previous, 2 = the one before that)
EXEC xp_readerrorlog 0, 1;          -- SQL Server log, current file
EXEC xp_readerrorlog 1, 1;          -- SQL Server log, previous file

-- Filter to AG-related messages only
EXEC xp_readerrorlog 0, 1, N'availability', NULL, NULL, NULL, N'desc';

-- Filter to a time window (last 2 hours)
DECLARE @start DATETIME = DATEADD(HOUR, -2, GETDATE());
EXEC xp_readerrorlog 0, 1, NULL, NULL, @start, NULL, N'desc';