Red Hat Enterprise Linux 6

Virtualization Host Configuration and Guest Installation Guide

Installing and configuring your virtual environment

Jiri Herrmann

Red Hat Customer Content Services

Tahlia Richardson

Red Hat Customer Content Services

Dayle Parker

Red Hat Customer Content Services

Laura Bailey

Red Hat Customer Content Services

Scott Radvan

Red Hat Customer Content Services

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This guide covers KVM packages, compatibility and restrictions. Also included are host configuration details and instructions for installing guest virtual machines of different types, PCI device configuration and SR-IOV.
1. Introduction
1.1. What is in This Guide?
2. System Requirements
3. KVM Guest Virtual Machine Compatibility
3.1. Red Hat Enterprise Linux 6 Support Limits
3.2. Supported CPU Models
4. Virtualization Restrictions
4.1. KVM Restrictions
4.2. Application Restrictions
4.3. Other Restrictions
5. Installing the Virtualization Packages
5.1. Configuring a Virtualization Host Installation
5.2. Installing Virtualization Packages on an Existing Red Hat Enterprise Linux System
6. Guest Virtual Machine Installation Overview
6.1. Guest Virtual Machine Prerequisites and Considerations
6.2. Creating Guests with virt-install
6.3. Creating Guests with virt-manager
6.4. Creating Guests with PXE
7. Installing a Red Hat Enterprise Linux 6 Guest Virtual Machine on a Red Hat Enterprise Linux 6 Host
7.1. Creating a Red Hat Enterprise Linux 6 Guest with Local Installation Media
7.2. Creating a Red Hat Enterprise Linux 6 Guest with a Network Installation Tree
7.3. Creating a Red Hat Enterprise Linux 6 Guest with PXE
8. Virtualizing Red Hat Enterprise Linux on Other Platforms
8.1. On VMware ESX
8.2. On Hyper-V
9. Installing a Fully-virtualized Windows Guest
9.1. Using virt-install to Create a Guest
10. KVM Paravirtualized (virtio) Drivers
10.1. Installing the KVM Windows virtio Drivers
10.2. Installing the Drivers on an Installed Windows Guest Virtual Machine
10.3. Installing Drivers during the Windows Installation
10.4. Using the virtio Drivers with Red Hat Enterprise Linux 3.9 Guests
10.5. Using KVM virtio Drivers for Existing Devices
10.6. Using KVM virtio Drivers for New Devices
11. Network Configuration
11.1. Network Address Translation (NAT) with libvirt
11.2. Disabling vhost-net
11.3. Bridged Networking with libvirt
12. PCI Device Assignment
12.1. Assigning a PCI Device with virsh
12.2. Assigning a PCI Device with virt-manager
12.3. Assigning a PCI Device with virt-install
12.4. Detaching an Assigned PCI Device
13. SR-IOV
13.1. Introduction
13.2. Using SR-IOV
13.3. Troubleshooting SR-IOV
14. KVM Guest Timing Management
14.1. Constant Time Stamp Counter (TSC)
14.1.1. Configuring Hosts without a Constant Time Stamp Counter
14.2. Required Parameters for Red Hat Enterprise Linux Guests
14.3. Using the Real-Time Clock with Windows Server 2008, Windows Server 2008 R2, and Windows 7 Guests
14.4. Steal Time Accounting
15. Network Booting with libvirt
15.1. Preparing the Boot Server
15.1.1. Setting up a PXE Boot Server on a Private libvirt Network
15.2. Booting a Guest Using PXE
15.2.1. Using Bridged Networking
15.2.2. Using a Private libvirt Network
16. Registering the Hypervisor and Virtual Machine
16.1. Installing virt-who on the Host Physical Machine
16.2. Registering a New Guest Virtual Machine
16.3. Removing a Guest Virtual Machine Entry
16.4. Installing virt-who Manually
16.5. Troubleshooting virt-who
16.5.1. Why is the hypervisor status red?
16.5.2. I have subscription status errors, what do I do?
A. NetKVM Driver Parameters
A.1. Configurable Parameters for NetKVM
B. Common libvirt Errors and Troubleshooting
B.1. libvirtd failed to start
B.2. The URI Failed to Connect to the Hypervisor
B.2.1. Cannot read CA certificate
B.2.2. Failed to connect socket ... : Permission denied
B.2.3. Other Connectivity Errors
B.3. The guest virtual machine cannot be started: internal error guest CPU is not compatible with host CPU
B.4. Guest starting fails with error: monitor socket did not show up
B.5. Internal error cannot find character device (null)
B.6. Guest virtual machine booting stalls with error: No boot device
B.7. Virtual network default has not been started
B.8. PXE Boot (or DHCP) on Guest Failed
B.9. Guest Can Reach Outside Network, but Cannot Reach Host when Using macvtap Interface
B.10. Could not add rule to fixup DHCP response checksums on network 'default'
B.11. Unable to add bridge br0 port vnet0: No such device
B.12. Guest is Unable to Start with Error: warning: could not open /dev/net/tun
B.13. Migration Fails with Error: unable to resolve address
B.14. Migration Fails with Unable to allow access for disk path: No such file or directory
B.15. No Guest Virtual Machines are Present when libvirtd is Started
B.16. Unable to connect to server at 'host:16509': Connection refused ... error: failed to connect to the hypervisor
B.17. Common XML Errors
B.17.1. Editing Domain Definition
B.17.2. XML Syntax Errors
B.17.3. Logic and Configuration Errors
C. Revision History