Alternatively, try guessing the drive ID if you know the slot number (e.g., slot 0 is usually 0 ). 2. Run the Corrected smartctl Command
By using the sat+megaraid,N flag with smartctl , you can bypass the controller emulation and properly monitor the health of your physical drives, ensuring reliable data storage.
Here's the general syntax:
storcli (Storage Command Line Tool) is the modern utility for Broadcom/LSI/Dell MegaRAID controllers. storcli show Use code with caution. (Take note of your controller ID, usually c0 ) List all physical drives: storcli /c0/eall/sall show Use code with caution. Alternatively, try guessing the drive ID if you
Or:
smartctl -a -d megaraid,N /dev/sda
| Action | Command | | :--- | :--- | | Basic access to a physical disk behind a RAID controller | sudo smartctl -a -d megaraid,N /dev/sda | | Scan for all accessible devices | sudo smartctl --scan | | List device IDs using storcli (most reliable) | sudo storcli /c0 /eall /sall show | | Legacy method: list device IDs with MegaCli64 | sudo /opt/MegaRAID/MegaCli/MegaCli64 -PDList -aALL \| grep "Device Id" | | Test all possible device IDs (0–30) | for i in 0..30; do echo "megaraid,$i"; sudo smartctl -i -d megaraid,$i /dev/sda; done | | Access for SATA disks using SAT passthrough | sudo smartctl -a -d sat+megaraid,N /dev/sda | | Run a short self‑test | sudo smartctl -t short -d megaraid,N /dev/sda | | Run a long self‑test | sudo smartctl -t long -d megaraid,N /dev/sda | | Check self‑test progress | sudo smartctl -c -d megaraid,N /dev/sda | | View self‑test results | sudo smartctl -l selftest -d megaraid,N /dev/sda | Here's the general syntax: storcli (Storage Command Line
If you are inside a virtual machine (VM) and the RAID controller is passed through to the host (e.g., Proxmox, ESXi), the VM will only see the virtual disk and usually cannot access the physical drives. You must run smartctl on the operating system to access the physical drives, not from inside the VM.
If your drive is part of a RAID 0, 1, or 5 array, smartctl will show the health of the logical volume. If it is in JBOD (Just a Bunch Of Disks) mode, sat+megaraid works best.
This happens because the controller intercepts all communication to protect the RAID array's integrity. For hardware RAID environments like Dell PowerEdge servers with PERC controllers or other LSI-based MegaRAID cards, smartctl requires a special -d megaraid,N syntax. The N value is a non-negative integer (usually 0 to 127) that identifies the specific physical disk to query. Or: smartctl -a -d megaraid,N /dev/sda | Action
Virtual arrays do not natively support physical Self-Monitoring, Analysis, and Reporting Technology (SMART) pass-through structures. Passing a raw geometry command down a generalized block route breaks at the controller level, generating the diagnostic message prompting for specific device arguments.
After running smartctl -a -d megaraid,0 /dev/sda , you might see:
#!/bin/bash LOGICAL_DEV="/dev/sda" MAX_DISKS=32 # Adjust based on max expected drives
smartctl -H /dev/sda smartctl: open device: /dev/sda failed: No such file or directory
(Just shows identity, no destructive action.)