Corrupted | Vmdk
# Check for zeroed CID (Corruption flag) CID=$(grep "CID=" $vmdk | cut -d'=' -f2) if [ "$CID" == "fffffffe" ]; then echo "ALERT: $vmdk has invalid CID. Possible corruption." >> $LOG_FILE /usr/bin/vmkfstools -x check $vmdk >> $LOG_FILE fi
#!/bin/bash # vmdk_integrity_check.sh # Checks for early signs of VMDK corruption DATASTORE_PATH="/vmfs/volumes/VM_Storage" LOG_FILE="/var/log/vmdk_health.log"
I open the server01.vmdk (descriptor file) in a terminal. vmdk corrupted
# Disk DescriptorFile version=1 CID=fffffffe parentCID=fffffffe createType="vmfs" RW 419430400 VMFS "server01-flat.vmdk"
The CID (Content ID) was reset to fffffffe — a flag meaning "unknown or corrupted parent." The flat extent is intact, but the mapping is blind. # Check for zeroed CID (Corruption flag) CID=$(grep
if [ ! -z "$FLAT_SIZE" ]; then CALC_MB=$(($FLAT_SIZE / 1024 / 1024)) echo "Health: $vmdk is $CALC_MB MB nominal." >> $LOG_FILE fi done VMDK corruption is rarely a hardware failure. It is a timing failure —where the hypervisor assumes a write completed before the storage array confirms it. The fix involves bypassing the broken descriptor and forcing a rebuild from the raw extent. Always keep a backup of the .vmdk descriptor file separately from the flat file.
vmkfstools -x repair /vmfs/volumes/datastore01/server01/server01.vmdk Output: "Failed to repair disk. Disk chain is inconsistent." The fix involves bypassing the broken descriptor and
Scenario: VMware ESXi environment, version 7.0.3. VM: Legacy SQL Server.