Category: XEN

List of XEN Virtualization tips and tricks

Linux, XEN

pygrub: Unable to find partition containing kernel

Introduction: Lately after I upgraded many packages in a Xen 4.4 DOMU VM the pygrub could not boot the VM any more. During the security update, the installed grub2(grup-pc), which never created any problems before with pygrub, got updated and suddenly it did create problems to boot the VM. Here is the error message I …

Linux, XEN

‘init: plymouth-upstart-bridge main process ended, respawning’ error messages at boot.

I installed a new Ubuntu 14.04 as a Xen server and found out that on booting the following messages repeated itself many times, [ 2.811553] init: plymouth-upstart-bridge main process (191) terminated with status 1 [ 2.812789] init: plymouth-upstart-bridge main process ended, respawning [ 2.874117] init: plymouth-upstart-bridge main process (210) terminated with status 1 [ 2.875167] …

Linux, XEN

Installing Xen Hypervisor 4.8 on Debian Jessie

Introduction: I was looking for a way to install Xen 4.8 in Jessie because in some of the newest Processors Intel series called Skylake the default version of Xen Hypervisor on Jessie (4.4) results in endless booting loops. NOTE: If you already had the Xen 4.4(original installed) no worries the version 4.4 will not be …

Linux, Systemd, XEN

Ubuntu 16.10 : xenconsole: Could not read tty from store: Success

Introduction: After having had some stability problems, with running Xen DOMUs under Ubuntu 16.04/Xen 4.6, I decided to upgrade to Ubuntu 16.10/Xen 4.7. Unfortunately, as I tried to start any of the DOMUs with the option -c to see the console content, the following error message was displayed and I got kicked out and no …

Linux, XEN

Creating a new Xen Debian virtual machine from scratch

Introduction: In this tutorial a new virtual machine based on Debian Jessie distribution will be created from scratch with minimal components. Assumption: The Xen Hypervisor should already be installed and running in the main system (DOM0). Creating the Xen Virtual Machine This virtual machine will be created with the xen tools which bootstraps the creation …

Linux, XEN

Installing Xen 4.4 on Ubuntu Server 14.04 LTS (Trusty)

Introduction: This HowTo assumes that the Internet access from VMs via DOM0 and the private LAN are done using the Bridge method. In the previous versions of Xen installation the bridges were dynamically built via the Xen scripts, in this version the bridges are built permanently as the DOM0 boots up. DOM0:xenbr0(eth0) —bridging==>> DOMUs:eth0 DOM0:pdummy0(dummy0) …

Bash, Linux, VMWare, XEN

Extending dynamically Linux RAMs in VMWare VM without rebooting

Situation: Need to raise the amount of RAM in a VMWare VM without rebooting. Solution: – In VMWare interface: Raise the amount of RAM for the VM – In the Linux VM: Run the following script: #!/bin/bash # This script enables in system the unrecognized RAMs deleteline () { echo -ne $dellineup } ### check …

Linux, VMWare, XEN

Update the number of CPU dynamically in a VMWare VM

Situation: I’ve come across a situation where I needed to LIVE-raise the number of CPUs for a VMWAre Linux VM without having to reboot. Solution: – In VMAre ris the number of CPUs – In the Linux VM do the following: – Save the following script into /root/bin/ directory (It was take from this article: …

Linux, XEN

Installing Xen 4.4 on Ubuntu Server 14.04 LTS (Trusty) in a Hetzner server with 8 IPs subnet

Hetzner Germany has very fast and not expensive rentals of Hardware servers available. In order to communicate internally via private network between Xen-DOMUs and DOM0, normally one would install Xen DOM0 network with bridge networking as follows: DOM0:xenbr0(eth0) ===bridging===>> DOMUs:eth0 BUT!!!! PROBLEM: Because of the configuration of the network switches at Hetzner, one hardware server …

Linux, XEN

Install Xen 4.1 on Debian Wheezy in a Hetzner Dedicated server

Hetzner Germany has very fast and not expensive rentals of Hardware servers available. In order to communicate internally via private network between Xen-DOMUs and DOM0, normally one would install Xen DOM0 network with bridge networking as follows: DOM0:xenbr0(eth0) — bridging==>> DOMUs:eth0 DOM0:xenbr1(dummy0) —bridging==>> DOMUs:eth1 BUT!!!! PROBLEM: Because of the configuration of the network switches at …

Linux, XEN

Switching from xm(xend) XenToolStack to XL XenToolStack in Delian Wheezy

Introduction: While I upgraded my Xen DOM0 from Squeeze to Wheezy it was recommended to switch from the Xend(xm) Toolstack to XL Toolstack. Because I found very little info on how to do the switch. So here is a way do it on Wheezy. Here we are assuming that you have installed Xen 4.1 Hypervisor …

Apache, Linux, Postfix, XEN

Creating a XEN machine and Installing Group Office in Debian Wheezy

Introduction In this Tutorial I will explain the steps I did to create a Xen Virtual Machine with minimal packages and then install the latest Group Office Web based Collaboration software. You’ll need to be fluent in Linux and Xen because I don’t explain much here. Note: My hypervisor is Xen 4.0 in Debian Squeeze …

Linux, XEN

Configuring Debian Wheezy Xen 4.1 Hypervisor

Introduction: When I upgraded from Debian Lenny Xen 3.2.1 to Squeeze Xen 4.0, except for the DOMu hard disks names (from /dev/hdax to /dev/xvdax), I had very little changes to do and all went pretty well. Lately I wanted to upgrade from Squeeze Xen 4.0 to Wheezy Xen 4.1 and I had a few very …

Linux, XEN

Basics of Linux Logical Volume Manager

Concept: Physical Volume(PV): Real partition which can be assigned to a pool of resource to create/manage logical volumesLogical Volume Group(LG): Pool of resources (partitions) which can be used to create/manage Logical volumesLogical Volumes(LV): Logical Partitions which can be formatted and used just like a normal partition. The difference is that these Logical Partitions can be …

Linux, XEN

Installing an Ubuntu 12.0.4 LTS as Xen DOMu in Debian Squeeze hypervisor

Lately I needed to install Zimbra 8.0.3 which only installs easily in an Ubuntu 10.0.4 or 12.0.4 LTS system. So I decided for that to install an Ubuntu 12.0.4 LTS as Xen DOMu in a Debian Squeeze Xen Hypervisor and here is how I did it. The following commands can be put into a runnable …

Linux, XEN

Using pyGRUB on Squeeze/Wheezy to boot a domU kernel

This adapded article is based on the following Debian Wiki article: http://wiki.debian.org/PyGrub In this article I assume: – The reader is familiar with Linux and Xen Hypervisor – The DOMu system partition is using a file image instead of a physical partition. Introduction: This method offers the advantage of loading the kernel which is installed …

Linux, XEN

Creating a new Xen DOMU Debian Squeeze image file(bootstrapping)

Here is a short example with many options given which creates a new Debian Squeeze Xen 4.0x image file. The command will create a 25GB Debian Squeeze Image file in the LVM:’vservers’ which will run the 32 bit kernel 2.6.26-2-xen-686 with 2GB of RAM and 1GB of SWAP file with root password ‘changeme’. Note: remember …

XEN

Create a mixed (routed & bridged) private VLAN for Xen Virtual Machines

The most common way of configuring the networking in Xen environment is by using bridges. In the case of servers rented at Hetzner provider (Germany) this would not work because the infrastructure is allowing only one MAC address per server. It allows for multiple IPs but only one MAC address. To circumvent this situation we …

Linux, XEN

Installing Xen 4.x in Debian Squeeze (6.0)

Here are the minimum steps necessary to install Xen Hypervisor 4.x on Debian Squeeze. Installing the hypervisor and tools related aptitude install xen-linux-system-2.6-xen-amd64 xen-hypervisor-4.0-amd64 linux-image-xen-amd64 xen-qemu-dm-4.0 Change some system configuration Edit /etc/modules and add the following entry. To make sure the module ‘loop’ can create 64 loop connections. The entry ‘loop’ might already be there, …

Linux, XEN

Assigning CPUs to Xen virtual Machines

Introduction: I’m renting a 8 CPU machine at Hetzner and I wanted to improve the performance. At the beginning I was distributing many CPUs to the virtual machines which needed it and less cpus to others. This included that some cpus would be shared by more than one Xen virtual machine. I noticed that the …