Run the following SQL query within the SQL*Plus environment of the affected ASM instance to identify the disk group's operational mode:
# Locate your ASM Alert log using the ADRCI tool adrci> show alert -p "message_text like '%ASM Health Checker%'" Use code with caution. 2. Verify Your Current Disk Group Status
Slow response times from the storage subsystem cause the Oracle ASM instance to drop the impacted disks. asm health checker found 1 new failures updated
Re-scans, OS reboots, or sector size changes ( ORA-15085 ) on the SAN break the shared storage layer. 📋 Comprehensive Troubleshooting Guide
The Oracle Automatic Storage Management (ASM) Health Checker periodically polls the storage environment's overall health. Below are the most common scenarios that trigger this alert: Run the following SQL query within the SQL*Plus
SELECT group_number, name, state, type, total_mb, free_mb FROM v$asm_diskgroup; Use code with caution.
Too many offline disks in the PST disable the read quorum, triggering a forced dismount. Re-scans, OS reboots, or sector size changes (
The disk group has dropped offline. This indicates a loss of disk quorum. 3. Check for Ongoing Rebalance Operations
Intermittent loss of connectivity to the SAN/LUNs causes heartbeat timeout warnings (e.g., Waited 15 secs for write IO ).