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kernel modules

Linux: Find Wireless Driver Chipset Information

How do I find out Wireless driver chipset information under a Linux operating system? How do I get wireless card chipeset information without opening my systems or laptop using a Linux?
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Fedora Linux Install Linux Kernel Headers And Developer Files

I‘m trying to install vmware-tools but Fedora Linux v12 prompting for kernel headers. How do I install kernel headers under Fedora Linux?
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Linux: Find out what kernel drivers (modules) are loaded

How do I find out what Linux kernel drivers are loaded by Linux? How do I list device drivers (or so-called modules) loaded into memory?
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Suse Linux install vmware tools

Q. I’m using OpenSuse as Guest OS (VPS). Installing SUSE Linux as a VMware Workstation guest operating system was easy task. But how do I setup and install SUSE Linux as a VMware Guest? How do I install vmware tools to improve performance?

A. In order to install Vmware tools, you need to build kernel modules. Building kernel modules is easy provided that following packages are installed on the guest OpenSuse / Suse Linux (VPS):

=> kernel-source

=> binutils

=> make

=> gcc

=> gcc-c++

Install required software

Login to guest oses using SSH or Vmware server console. Use yast command (yast control center) to install required software:
# yast
Select Software > Software management > Add above packages > Accept and install the softwares
The Software Management tool in YaST text mode
(YaST text mode software installation)

If you are using a GUI, you should see screen as follows (YaST2 screen):
YaST2 GUI

Start VMWARE Tools installation

You need to start VMware tools installation from Vmware server console or Vmware Workstation VM menu.
Click on VM Menu > Select Install Vmware Tools… > Click on Install
Start VMWARE Tools installation

Mount the VMware Tools virtual CD

If you are using guest system’s desktop, you should have mounted a CD. If you are using text mode, run mount command as follows:
# mount /dev/hdc /media
Output:

mount: block device /dev/hdc is write-protected, mounting read-only

Replace /dev/hdc with actual virtual cd rom drive.

Install the VMware Tools RPM

Finally install rpm file,
cd /media
ls
rpm -ivh VMwareTools-1.0.3-44356.i386.rpm

Configure Vmware tools

Next you need to run the VMware Tools configuration script. You must run script from VMWare server console / Workstation and not from SSH session:
# vmware-config-tools.pl
OR
# vmware-config-tools.pl -default

Sun Solaris UNIX display list for loaded kenel device driver / modules

Q. How do I display information about loaded kernel modules under Sun Solaris UNIX operating system?

A. You need to use modinfo command which is a trivial program to display information about the loaded modules. The format of the information is as follows:

Id Loadaddr Size Info Rev Module Name

where Id is the module ID, Loadaddr is the starting text address in hexadecimal, Size is the size of text, data, and bss in hexadecimal bytes, Info is module specific information, Rev is the revision of the loadable modules system, and Module Name is the filename and description of the module.

Task: Displaying the status of kernel modules

Just enter modinfo command:
modinfo
You can pass -c option to modinfo command to display the number of instances of the module loaded and the module’s current state:
modinfo -c

Display information about particular module / driver only

You can also display information about particular module only by specifying its ID #:
modinfo -i 5
The above example displays the status of module # 5.

Read modinfo man page for other information and options.

Howto: Linux Add or Remove a Linux Kernel Modules / Drivers

How do I add or remove hardware device driver (module) from running Linux kernel?
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Linux Kernel panic VFS Unable to mount root fs and solution

Q. I am using Linux on HP server and I am getting error that read as follows:
Linux Kernel panic: VFS: Unable to mount root fs

How do I solve this problem?

A. Most modern distributions including Debian uses loadable kernel module for ext3 file system. So to read ext3/ext2 file system kernel must load ext3 kernel module (ext3.ko).

This module is included in an initrd image. If an initrd image is missing or that image does not include suitable kernel modules to access the ext3 filesystem on the partition, an error message (Linux Kernel panic: VFS: Unable to mount root fs) will be displayed to you.

To solve this problem you need to use mkinitrd script that constructs a directory structure that can serve as an initrd root file system.

The instructions for creating initrd images are here on our site.

Linux rebuild the initial ramdisk image

Q: I think I am missing some driver or my initial ramdisk is corrupted for running kernel how do I Rebuild the initial ramdisk image under Linux?

A: You need ramdisk if you have added new hardware devices such as SCSI or FibreChannel controller to your server as the ramdisk contains the necessary modules (i.e. drivers) to initialize hardware driver. If you modified the /etc/modprob.conf (or modules.conf) file then you need to execute special script called mkinitrd.

The mkinitrd script constructs a directory structure that can serve as an initrd root file system. It then generates an image containing that directory structure using mkcramfs, which can be loaded using the initrd mechanism. The kernel modules for the specified kernel version will be placed in the directory structure. If version is omitted, it defaults to the version of the kernel that is currently running.

Find out your kernel version:
# uname -r
2.6.15.4
Make backup of existing ram disk:
# cp /boot/initrd.$(uname -r).img /root
To create initial ramdisk image type following command as the root user:
# mkinitrd -o /boot/initrd.$(uname -r).img $(uname -r)
# ls -l /boot/initrd.$(uname -r).img

You may need to modify grub.conf to point out to correct ramdisk image, make sure following line existing in grub.conf file:
initrd /boot/initrd.img-2.6.15.4.img
When the system boots using an initrd image created by mkinitrd command, the linuxrc will wait for an amount of time which is configured through mkinitrd.conf, during which it may be interrupted by pressing ENTER. After that, the modules specified in will be loaded.