open /dev/mptctl: No such device. Make sure mptctl is loaded into the kernel

The “mptctl” kernel module is required to check the RAID status on a Linux server using “mpt-status” tool.

You may receive “/dev/mptctl: No such device” message OR “Make sure mptctl is loaded into the kernel” while checking the RAID status which indicates that the module is not loaded in the kernel OR the device “/dev/mptctl” is not created.

# mpt-status 
 open /dev/mptctl: No such device 
 Are you sure your controller is supported by mptlinux? 
 Make sure mptctl is loaded into the kernel

To create the mptctl device, execute:

# mknod /dev/mptctl c 10 22

and verify it by

# ls -la 
 /dev/mptctl crw------- 1 root root 10, 220 Apr 12 08:05 /dev/mptctl

Once the device is created, load the module in the kernel using modprobe

# modprobe mptctl

and verify it using lsmod which should list the following modules along with it’s details

# lsmod |grep mptctl 
 mptctl 
 mptbase 
 scsi_mod

Add the module in /etc/rc.modules file to load the module in kernel on every reboot.

modprobe mptctl

Save the file. This will make sure the module is loaded in the kernel on every server reboot.

Once done, you will be able to check the RAID status by executing the ‘mpt-status’ command and it should show something like the following:

# mpt-status
 ioc0 vol_id 0 type IM, 2 phy, 465 GB, state OPTIMAL, flags ENABLED 
 ioc0 phy 1 scsi_id 1 ATA ST3 CC38, 10 GB, state ONLINE, flags NONE 
 ioc0 phy 0 scsi_id 4 ATA ST3 CC38, 10 GB, state ONLINE, flags NONE
This entry was posted on Friday, May 21st, 2010 and is filed under Linux Administration. You can follow any responses to this entry through the RSS 2.0 feed. Both comments and pings are currently closed.

One Response to “open /dev/mptctl: No such device. Make sure mptctl is loaded into the kernel”

  1. queo

    Thanks very much for this tip!

    Best regards,
    queo