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 …
Category: XEN
List of XEN Virtualization tips and tricks
‘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] …
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 …
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 …
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 …
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) …
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 …
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: …
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 …
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 …
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 …
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 …
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 …
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 …
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 …
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 …
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 …
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 …
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, …
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 …
Xen routed ext/int(virtual private) networking at Hetzner under Debian Lenny/Squeeze 64 Bit
At Hetzner(Germany) you can rent quite hot machines for a very good price. But what happens when you want to set-up multiple Xen virtual machines? You might get into trouble unless you follow these instructions. They are probably not the only solution for a well working xen machines farm but this one worked well for me.
Create a (bridged) VLAN for Xen Virtual Machines
To create a virtual private LAN which allows to communicate between Xen virtual machines (DOMx) via eth1 including the DOM0(dummy0), follow these instructions. This will create a bridge in xen DOM0 and a new interface(eth1) in the DOMx (in our case ‘vsystem1’). NOTE: This method implies that the eth0 is also bridged. In case you …
Troubleshooting no root login possible from Xen console
If you can’t login as root from the Xen console on a DomU then do the following: – stop the DomU – Mounted it on a directory through loop mount -o loop,rw /where/my/DomU/image.is /mnt/domu/ – chroot to it chroot /mnt/domu/ – Install the udev package. (it complains at the end..but no worry) apt-get install udev …
chroot inside xen VM VDSO problem
If inside a xen machine you try to do a chroot into a directory and get this error: Inconsistency detected by ld.so: rtld.c: 1192: dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso’ failed! One of the possible solutions is to use the following command before issuing the chroot. echo 0 >/proc/sys/vm/vdso_enabled It is supposed to have …
Installing Webmin based Xen Virtual Machines Control Panel
I know it’s totally an overkill to install Webmin to be able to freely and remotely control some basic features of the xen virtual Machines. But so far I haven’t found a really simple and decent replacement for it. Let me know if you do: michel@linuxint.com It took me a little while to find the …
Troubleshooting PTY allocation request failed on channel 0
This is an extract from a tip from ‘Xen Virtualization community support and Howto’s.‘. Thanks guys. It saved my but. When installing new virtual machine on a Debian “Lenny” host, You might get the following error message once you try SSH the new domU: PTY allocation request failed on channel 0 stdin: is not a …
Installing Windows 2003/XP/7 32 Bit on Xen in Debian Squeeze 64 Bit.
The task here is to install, run and administrate Windows 2003/XP/7 on a remote server in Internet where Xen 4.x is already installed and HVM is supported in hardware. The steps to install and run Windows are slightly different than for Linux Guests OS. In these cases Q Emu virtualization drivers are needed to complete …
Change memory size while running XEN vMachine
While running you can change the live memory size of a VM or the Domani-0 (although may be dangerous for crashes) Use the command: xm mem-set ID NewMEMSize
Stop/Start a single XEN virtual machine
Assuming that the virtual machine is running, to stop the machine: – Make a list of the running virtual machines and note the ID of the one concerned. xl list Lets suppose the ID of the virtual machine concerned is 15 – Shutdown the machine. xl shutdown 15 – Make a few xm list commands …
Resizing XEN virtual image
Question: I am using Xen to create Virtual Machines, but how can I re-size the virtual disk image? Solution: Add an extra empty space to your virtual disk size and re-size the filesystem in it: or if reducing is needed, minimize the files system, add empty space to it as desired and re-size it. Example …