Installing the Nvidia driver on the latest Fedora

I found it very hard to find a guide to properly disable the nouveau driver so I can install the Nvidia driver on Fedora 20. This should help simplify the installation.

1. Install the kernel-devel and development packages for your running kernel.

yum -y install kernel-devel-`uname -r` kernel-headers-`uname -r`
yum groups mark-install “Development Tools”
yum groups install “Development Tools”

2. Blacklist the nouveau driver. This needs to be done to properly load the Nvidia driver. First, the module must be blacklisted on the system. The final step is to remove the nouveau driver from the kernel ram disk image.

echo “blacklist nouveau” >> /usr/lib/modprobe.d/dist-blacklist.conf

dracut -f -o nouveau

3. Boot into runlevel 3 with “nomodeset” on the kernel line in grub.cfg or add it to the kernel line in the grub boot menu. If you do not do this, you will see a black screen when you reboot.

4. Run the Nvidia installer

5. Reboot.

Compiling the latest Linux kernel

I felt like getting back into trying the latest kernel and wrote this article on how to compile the latest
Linux kernel from kernel.org. This was done on a machine running Fedora 20.

1. Download the sources from kernel.org

# wget https://www.kernel.org/pub/linux/kernel/v3.x/linux-3.14.tar.xz
Continue reading Compiling the latest Linux kernel

Installing OpenStack on CentOS

I finally got OpenStack installed correctly after struggling with their documentation and the guides online. I wanted to share these steps with the everyone to ease the pain.

 

1. Install Epel Repo

 

wget http://dl.fedoraproject.org/pub/epel/6/x86_64/epel-release-6-8.noarch.rpm

wget http://rpms.famillecollet.com/enterprise/remi-release-6.rpm

rpm -Uvh remi-release-6*.rpm epel-release-6*.rpm

 

Continue reading Installing OpenStack on CentOS

Improving IO performance on Linux

I purchased a new server and have been struggling with IO performance on a RAID 1 setup. I first tried RAID 5 but it was horrible. Through all my struggles, I found a few kernel and filesystem tunables that helped me out.

The virtual machines improved also. They were barely usable.

Filesystem Tweaks: /etc/fstab

Change your mount options to:

defaults,noatime,data=writeback,barrier=0,nobh
Linux Kernel tunables:
sysctl -w vm.swappiness=0
sysctl -w vm.dirty_background_ratio=5
sysctl -w vm.dirty_ratio=5
sysctl -w vm.vfs_cache_pressure=200
The dirty tunables controls the portion of memory that the kernel will store pages in. I decreased the value to 5 so that I will have more memory free.  The cache_pressure tunable tells the kernel how to quickly free up the cache.

NIS server and client tutorial with AutoFS (CentOS / Arch Linux)

I use both Arch and CentOS in my environment so I made this  easy tutorial that will show you how to setup a NIS client/server on Arch Linux and CentOS.

*NIS Clients will not need ypserv*

Arch Linux:
# pacman -S ypbind-mt yp-tools ypserv autofs
CentOS: 
# yum -y install ypbind rpcbind ypserv autofs

How to clone a KVM virtual machine on Linux

First, select the virtual machine that you want to clone.

 

[root@redhat ~]# ls /etc/libvirt/qemu/*.xml

/etc/libvirt/qemu/cp1.xml     /etc/libvirt/qemu/vcs5_sol_n1.xml      /etc/libvirt/qemu/vcs6_lin_vvr_n3.xml

/etc/libvirt/qemu/rhel6.xml   /etc/libvirt/qemu/vcs6_lin_vvr_n1.xml  /etc/libvirt/qemu/vcs6_sol_n1.xml

/etc/libvirt/qemu/rusher.xml  /etc/libvirt/qemu/vcs6_lin_vvr_n2.xml

Continue reading How to clone a KVM virtual machine on Linux

How to generate and analyze a crash dump on Redhat Enterprise Linux

This is a guide on how to gather a crash dump on RHEL systems.

 
First, install the following packages:

# yum install kexec-tools crash kernel-debuginfo kernel-debuginfo-common system-config-kdump
Continue reading How to generate and analyze a crash dump on Redhat Enterprise Linux