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Xen Articles

My server clock / date and time is wrong or drifts

First, determine your instance type.Select options from your Manage Servers screen and look at 'Virtualization type' under Advanced. If it is set to 'Fully Virtualized' follow the HVM instructions below. If it is set to use a PV-GRUB or PyGRUB boot loader use the PV instructions.For ...


Convert Gentoo HVM to PV

Follow these instructions to convert your Xen Gentoo HVM (Fuilly Virtualized) instance to a paravirtalized (PV) instance. This also works for physical machines.Note that if you've installed a Base Gentoo or other Gentoo PV image, you do not need to follow this guide. You may find the ...


Using MacOS to connect to a virtual machine with VNC

This article refers to settings that are out of date and have been replaced with our web console/web VNCWhy use VNC?VNC gives you 100%, complete out of band access to your server. If your server is ever in UP status, but not reachable, you can use VNC to connect and troubleshoot. ...


Xen PV Debian 6 kernel upgrade hang

If you perform an apt-get update and upgrade and your Debian 6 based xen kernel is updated and you reboot to find your system doesn't come back up, it's likely because the default 0 / timeout lines were removed from menu.lst.To make sure this doesn't happen either double check your ...


Convert Centos HVM to PV

 Follow these instructions to convert your Xen Centos HVM (Fuilly Virtualized) instance to a paravirtalized (PV) instance. This also works for physical machines.Note that if you've installed a Base Centos or other Centos PV image, you do not need to follow this guide.Reboot to a ...


Xen Centos 5.5 to 5.6 upgrade no network

In some cases yum updating your CentOS 5.5 paravirtualized (PV) or fully virtualized (HVM) instance causes a udev issue which prevents your system from coming back online after a reboot.This is because CentOS moves the /etc/sysconfig/network-scripts/ifcfg-eth0 file to ifcfg-eth0.bak. ...


Convert Ubuntu HVM to PV

Follow these instructions to convert your Xen Ubuntu HVM (Fuilly Virtualized) instance to a paravirtalized (PV) instance. This also works for physical machines. Note that if you've installed a Base Ubuntu or other Ubuntu images, you do not need to follow this guide. On ubuntu 10.04 to get ...


How to convert a Fedora Core 14 Xen HVM to PV

Fedora Core 14 includes a xen capable kernel by default. To convert your Xen HVM (Fully Virtualized) instance to a paravirtualized (PV) instance, simply change your bootloader to PV-GRUB64.If you're using our service, select your servers dashboard, go to options > advanced options, change ...


Xen Paravirt Ops

Xen paravirt_ops for upstream Linux kernel  What is paravirt_ops? paravirt_ops (pv-ops for short) is a piece of Linux kernel infrastructure to allow it to run paravirtualized on a hypervisor. It currently supports VMWare's VMI, Rusty's lguest, and most ...


Compile your custom gentoo kernel with xen support

 Follow these instructions to compile your custom gentoo kernel with xen support for your paravirtualized instance.This guide should help after you deploy a Gentoo PV base image and update it to boot with your custom kernel.Update portage & Install xen-sources ...


Gentoo hardened kernel with xen pv and gentoo xen pv config

Look at:  http://vr.org/files/gentoo-hardened.config for a hardened config, or  http://vr.org/files/gentoo-i386-pv.config and  http://vr.org/files/gentoo-x64-pv.configA working kernel based on gentoo-hardned.config above can be dropped in: ...


Enable disk quota in a xen pv kernel on CentOs

1. echo 'KERNEL=="sda1", SUBSYSTEM=="block", SYMLINK+="root"' > /etc/udev/rules.d/99-root-link.rules2. root entry in /etc/fstab should have:  defaults,noatime,usrquota,grpquota3. Load the quota_v2 module at boot: echo 'modprobe quota_v2' >> /etc/rc.modules; chmod +x /etc/rc.modules ...


CentOS 5.8 CSF and xen pv-grub based kernel

If you are having trouble with CSF failing tests like: perl /etc/csf/csftest.plTesting ip_tables/iptable_filter...OKTesting ipt_LOG...OKTesting ipt_multiport/xt_multiport...OKTesting ipt_REJECT...OKTesting ipt_state/xt_state...OKTesting ipt_limit/xt_limit...OK ...


Improve inter-vm transfer & performance on Xen Hypervisors

If you are experiencing slow throughput between one or more virtual machines on a Xen hypervisor, the following will resolve the issue:ethtool -K eth0 tx offTo ensure the command is applied at boot, add it to your /etc/rc.local file.You can run it and add it ...


DirectAdmin quota error setquota Not all specified mountpoints are using quota

Error with system Quotassetquota: Mountpoint (or device) / not found. setquota: Not all specified mountpoints are using quota.Can be resolved with the following:ln -d /dev/xvda3 /dev/rootmount -o remount /Then run/sbin/quotaoff -a; /sbin/quotacheck ...


CentOS 6 pv-grub xen kernel for selinux and native kernel support

You can use pv-grub (i386 or x64) in CentOS 6.x to boot the stock CentOS kernel. Note that there is no longer a kernel-xen in CentOS since Redhat dropped Xen support, however Xen drivers are part of the mainline Linux kernel. To use PV-GRUB, edit /boot/grub/menu.lst - remove the standard ...


xen domU no suitable drive was found in the generated device map

If you are having issues with reinstalling grub and getting errors like hd0 does not exist or No suitable drive was found in the generated device map.<br> Boot to cloud kernel or chroot into the virtual machine, and then run the following (confirm drive name with fdisk -l first) # ...


Grub booting from hard disk hangs xen fully virtualized (hvm)

If are running under Fully Virtualized (xen HVM) mode and see a prompt that says "Booting from Hard Disk..." on your VNC console and your server never starts you likely need to reinstall grub.You can do that in a few simple steps: 1. Set cloud kernel to latest for your architecture in ...


Convert Ubuntu 14.04 HVM to PV

Follow these instructions to convert your Xen Ubuntu HVM (Fully Virtualized) instance to a paravirtualized (PV) instance. This also works for physical machines.Note: If you've installed a base Ubuntu or other Ubuntu paravirtualized PV image, you do not need to follow this ...


Reinstall grub from rescue mode

To reinstall grub in rescue mode, please boot to rescue mode and then enter the following: grub grub> device (hd0) /dev/xvda grub> root (hd0,0) grub> setup (hd0) grub> quit


Convert Debian 7.0 ( HVM to PV

Follow these instructions to convert your Xen Debian 7.0 ( Wheezy ) HVM (Fully Virtualized) instance to a paravirtualized (PV) instance. This also works for physical machines.Note: If you've installed a base Ubuntu or other Ubuntu paravirtualized PV image, you do not need ...


VPS kernel crashes with BUG: soft lockup - CPU#X stuck for YYs! [process/1:0]

#1 Update the system kernel by executing: Debian [root@hostname ~]# apt-get update && apt-get upgrade Centos [root@hostname ~]# yum upgrade Other See your distribution/OS documentation #2. Increase the watchdog timeout Check to determine which of ...