Table of Contents

KVM

Kernel-based Virtual Machine (KVM) is a virtual machine implementation using the operating system's kernel. This often allows for greater performance than when using virtual machine solutions which rely on user-space drivers.

Upon provisioning you'll have the option of either installing from a template or doing a manual install by ISO.

We recommend the templates whenever possible as they will include the latest updates and are slimmed down quite a bit.

Basic Install

Linux based templates will generate a randomized password.

Windows based templates will be syspreped and will ask you to setup an adminstrator user.

You must load the console and finish setup. You will also have to enable remote desktop from the Computer Properties page.

Limitations

Some operating systems are walled off depending on how much memory you have.

Templates can help get around some of these limits since, for instance, CentOS will request 256MB+ RAM during installation but will only use < 20MB when bootup. For CentOS you will need to use a template.

Windows 2003 will work on a 128MB with about 30MB spare RAM. Windows 2008 R2 & 2012 both require a minimum of 512MB RAM.

Networking

IPv4

Public

DHCP is hit or miss with KVM, if your networking fails to setup automatically please use the following information to configure it manually:

Here is a Debian example:

auto eth0
iface eth0 inet static
     address 45.59.69.155
     netmask 255.255.255.0
     gateway 45.59.69.1 

Private IP address

Dallas

Example configuration for Debian in Las Vegas
iface eth0 inet6 static
     address YOUR_IPV6_ADDRESS_HERE
     netmask 48
     gateway 2605:f700:80:40e::1
Example configuration for Debian in Dallas
iface eth0 inet6 static
     address YOUR_IPV6_ADDRESS_HERE
     netmask 48
     gateway 2605:f700:80:40e::1

Windows

Known Issues/Informational

Intel E1000 NIC Drivers

Pagefile/Swap Disclaimer

Please set reasonable Pagefile/Swap sizes as excessive IO caused by abusing these will result in suspension, repeated abuse will result in termination without credit nor refund.

Poor Disk Performance

You may be unsatisfied or have noticed poor I/O performance due to the fact that all KVM based VPS are provisioned with IDE based disks by default, this is required as not all OS play well with the VIRTIO BUS, namely Windows.

The VIRTIO driver floppy is automatically mounted with your VPS during bootup time so be sure to select the drivers off this disk when installing Windows.

Poor Network Performance On Linux

If your virtual server has < 512MB RAM you'll likely suffer poor network performance due to strict default buffer sizes.

To get around this please add the follow to your /etc/sysctl.conf

net.core.rmem_max=16777216
net.core.wmem_max=16777216
net.ipv4.tcp_rmem=4096 87380 16777216
net.ipv4.tcp_wmem=4096 65536 16777216

Once you're done this be sure to sysctl -p to apply it.

These settings will automatically apply during restarts so you shouldn't need to cron/script anything else.