Posts List

Installing stock CentOS kernel on an OVH or Kimsufi server

I recently signed up for a small dedicated server at for the grand price of £14 a month which I think is pretty good price for what you get. Brand Intel Model Celeron / Atom Frequency 1.20+ GHz Architecture 64 bits NIC

Set txqueuelen on virtual vnetX devices with libvirt

The txqueuelen is a value in the kernel on network interfaces that sets the transmit queue length. This value can be tuned for different work loads. In the case of modern networking the defaults can sometimes be changed to get better line speeds over ethernet. Most people will do this using a rc.local command to set it on the physical ethX devices like this. vim /etc/rc.local Add the following

Linux network bond without restarting the network

This is quite handy to know if you need to create a new network bond on a live system without disrupting traffic. First of all create your bond configs in the normal way so that in the event of a reboot it will come back up working. See the Redhat documentation for how to do it in RHEL6. Now because we cannot just restart the networking to bring that up we need to construct it by hand.

Reinstall CentOS using grub

This post is here mainly because I always forget how to do it. This is one of the simplest ways to reinstall a Centos (will probably work for RHEL and maybe even Fedora) system without needing PXE or physical access to the machine. Make sure that that you have tested you kickstart before you use it and don’t blame me if anything goes wrong. Save the following script and make it executable then run it.