The Alloy Wheel Fitment, Tyre Stretch, Rolling Radius & Speedo Error Calculator
megacli -ldinfo -lall
Drive Information : ================= ------------------------------------------------------- EID:Slt DID State DG Size Intf Med SED PI SeSz Model ------------------------------------------------------- 252:0 0 Onln 0 1.818 TB SATA HDD N N 512B ST2000NM0001 252:1 1 Onln 0 1.818 TB SATA HDD N N 512B ST2000NM0001 ------------------------------------------------------- Use code with caution.
First, ensure you have smartmontools installed and find the correct device node (usually /dev/sda or /dev/sgX ). You can use lsblk to list devices. 2. Probe the Drive Structure
Hardware RAID controllers present a single virtual drive to the operating system, which hides the raw SMART data of the individual physical disks. To bypass this, you must explicitly tell smartctl which physical disk on the controller you want to query using the -d megaraid,N flag. Step 1: Identify the Physical Device IDs
(Just shows identity, no destructive action.)
The error message gives a hint: "please try adding -d megaraid,N". This tells smartctl to pass through the RAID controller's management interface to reach the physical disks. 1. Identify the Controller and Devices
If your configuration routes consumer-grade or bulk enterprise SATA disks through a hardware RAID card, the control instruction must explicitly invoke a translation layer ( sat ) to ensure proper translation. Without appending this parameter, command outputs may drop attribute strings or report missing identification data: smartctl megaraid,N ( how to find the right value for N ? )
This error occurs when smartctl cannot directly access a physical disk ( /dev/sda ) because the disk is behind a or MegaRAID controller. The OS sees a virtual drive, not the raw physical disk.
List all physical disks in the RAID volume:
megacli -ldinfo -lall
Drive Information : ================= ------------------------------------------------------- EID:Slt DID State DG Size Intf Med SED PI SeSz Model ------------------------------------------------------- 252:0 0 Onln 0 1.818 TB SATA HDD N N 512B ST2000NM0001 252:1 1 Onln 0 1.818 TB SATA HDD N N 512B ST2000NM0001 ------------------------------------------------------- Use code with caution.
First, ensure you have smartmontools installed and find the correct device node (usually /dev/sda or /dev/sgX ). You can use lsblk to list devices. 2. Probe the Drive Structure
Hardware RAID controllers present a single virtual drive to the operating system, which hides the raw SMART data of the individual physical disks. To bypass this, you must explicitly tell smartctl which physical disk on the controller you want to query using the -d megaraid,N flag. Step 1: Identify the Physical Device IDs
(Just shows identity, no destructive action.)
The error message gives a hint: "please try adding -d megaraid,N". This tells smartctl to pass through the RAID controller's management interface to reach the physical disks. 1. Identify the Controller and Devices
If your configuration routes consumer-grade or bulk enterprise SATA disks through a hardware RAID card, the control instruction must explicitly invoke a translation layer ( sat ) to ensure proper translation. Without appending this parameter, command outputs may drop attribute strings or report missing identification data: smartctl megaraid,N ( how to find the right value for N ? )
This error occurs when smartctl cannot directly access a physical disk ( /dev/sda ) because the disk is behind a or MegaRAID controller. The OS sees a virtual drive, not the raw physical disk.
List all physical disks in the RAID volume:
Use our comprehensive online wheel size calculator to visualise different alloy wheels and tyre combinations. Calculate your offset, compare tyre stretch, rolling radius and more. Compare your new and existing setup and our tool will show you key measurements for accurate wheel and tyre fitment.
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