From e1587dfd0ab6a9fdc0f7c5186d51c6d2d6ad20f2 Mon Sep 17 00:00:00 2001 From: nerminamiller Date: Fri, 11 Oct 2013 12:16:06 -0400 Subject: [PATCH] Add KVM config info to the Install Guide Add KVM config info from Config Reference Update Enabling KVM in the native file Update the references to QEMU and Xen Create Enabling KVM section and use it from both Config Reference and Install Guide Add reference to amd and intel subsections Change-Id: I103ec048cceefb336026823a16257d88671bf969 Closes-Bug: #1238256 Author: Nermina Miller --- doc/common/section_kvm.xml | 391 +++++++++++-------------- doc/common/section_kvm_enable.xml | 101 +++++++ doc/install-guide/section_nova-kvm.xml | 82 +----- 3 files changed, 279 insertions(+), 295 deletions(-) create mode 100644 doc/common/section_kvm_enable.xml diff --git a/doc/common/section_kvm.xml b/doc/common/section_kvm.xml index 3eb9bf92b0..a90d87498c 100644 --- a/doc/common/section_kvm.xml +++ b/doc/common/section_kvm.xml @@ -5,248 +5,199 @@ xml:id="kvm"> KVM -KVM is configured as the default hypervisor for Compute. - There are several sections about hypervisor - selection in this document. If you are reading this - document linearly, you do not want to load the KVM - module prior to installing nova-compute. The - nova-compute service depends on qemu-kvm which - installs - /lib/udev/rules.d/45-qemu-kvm.rules, - which sets the correct permissions on the /dev/kvm - device node. - + KVM is configured as the default hypervisor for + Compute. + + This document contains several sections about hypervisor + selection. If you are reading this document linearly, you + do not want to load the KVM module before you install + nova-compute. + The nova-compute + service depends on qemu-kvm, which installs + /lib/udev/rules.d/45-qemu-kvm.rules, + which sets the correct permissions on the /dev/kvm device + node. + To enable KVM explicitly, add the following configuration - options - /etc/nova/nova.conf:compute_driver=libvirt.LibvirtDriver + options to the /etc/nova/nova.conf + file: + compute_driver=libvirt.LibvirtDriver libvirt_type=kvm - The KVM hypervisor supports the following virtual machine - image formats: - - Raw - - - QEMU Copy-on-write (qcow2) - - - QED Qemu Enhanced Disk - - - VMWare virtual machine disk format (vmdk) - - - The rest of this section describes how to enable KVM on your system. You may also wish to - consult distribution-specific documentation: - - Fedora: Getting started with virtualization from the Fedora project - wiki. - - - Ubuntu: - KVM/Installation from the Community Ubuntu documentation. - - - Debian: Virtualization with KVM from the Debian handbook. - - - RHEL: Installing virtualization packages on - an existing Red Hat Enterprise Linux - system from the Red Hat Enterprise - Linux Virtualization Host Configuration and Guest - Installation Guide. - - - openSUSE: Installing KVM from the openSUSE Virtualization with KVM - manual. - - - SLES: Installing KVM from the SUSE - Linux Enterprise Server Virtualization with KVM - manual. - - -
- Checking for hardware virtualization support - The processors of your compute host need to support virtualization technology (VT) - (mainly Intel VT -x or AMD AMD-v technologies) to use KVM. - In order to check if your processor has VT support (which has to be enabled in the - BIOS), follow on Ubuntu these steps: - - - Issue as root on Ubuntu: - # apt-get install cpu-checker -# kvm-ok - - - If KVM is supported, the output should look something like: -INFO: /dev/kvm exists -KVM acceleration can be used - - - If KVM is supported, the output should look something like: -INFO: /dev/kvm exists -KVM acceleration can be used - - - On other distributions, follow these steps: - - - Run the following as user: - $ egrep '(vmx|svm)' --color=always /proc/cpuinfo - - - If KVM is supported, the output should look something like: - flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx rdtscp lm constant_tsc arch_perfmon pebs bts rep_good nopl xtopology nonstop_tsc aperfmperf pni dtes64 monitor ds_cpl vmx est tm2 ssse3 cx16 xtpr pdcm pcid sse4_1 sse4_2 popcnt lahf_lm arat dtherm tpr_shadow vnmi flexpriority ept vpid - - - If KVM is not supported, you should get no output. - - - Some systems require that you enable VT support in the system BIOS. If you believe - your processor supports hardware acceleration but the above command produced no output, - you may need to reboot your machine, enter the system BIOS, and enable the VT - option. + The KVM hypervisor supports the following virtual machine + image formats: + + + Raw + + + QEMU Copy-on-write (qcow2) + + + QED Qemu Enhanced Disk + + + VMWare virtual machine disk format (vmdk) + + + This section describes how to enable KVM on your system. For + more information, see the following distribution-specific + documentation: + + + Fedora: Getting started with + virtualization from the Fedora project + wiki. + + + Ubuntu: KVM/Installation from the + Community Ubuntu documentation. + + + Debian: Virtualization with KVM from the + Debian handbook. + + + RHEL: Installing virtualization packages on an + existing Red Hat Enterprise Linux system + from the Red Hat Enterprise Linux + Virtualization Host Configuration and Guest + Installation Guide. + + + openSUSE: Installing KVM from the openSUSE + Virtualization with KVM manual. + + + SLES: Installing KVM from the SUSE Linux + Enterprise Server Virtualization with KVM + manual. + + - In the case that KVM acceleration is not supported, Compute should be configured to - use a different hypervisor, such as QEMU or Xen. + -
- -
- Enabling KVM - KVM requires the kvm and either kvm-intel or - kvm-amd modules to be loaded. This may have been configured - automatically on your distribution when KVM is installed. - You can check that they have been loaded using lsmod, as follows, - with expected output for Intel-based - processors:$ lsmod | grep kvm -kvm_intel 137721 9 -kvm 415459 1 kvm_intelThe - following sections describe how to load the kernel modules for Intel-based and AMD-based - processors if they were not loaded automatically by your distribution's KVM installation - process. - -
- Intel-based processors - If your compute host is Intel-based, run the following as root to load the kernel - modules:# modprobe kvm -# modprobe kvm-intel - Add the following lines to /etc/modules so that these modules - will load on reboot:kvm -kvm-intel -
-
- AMD-based processors - If your compute host is AMD-based, run the following as root to load the kernel - modules:# modprobe kvm -# modprobe kvm-amd - Add the following lines to /etc/modules so that these modules - will load on reboot:kvm -kvm-amd -
-
- Specifying the CPU model of KVM guests - The Compute service allows you to control the guest CPU model that is exposed to KVM - virtual machines. Use cases include: - - To maximize performance of virtual machines by exposing new host CPU - features to the guest - - - To ensure a consistent default CPU across all machines, removing reliance - of variable QEMU defaults - - - In libvirt, the CPU is specified by providing a base CPU model name (which is a - shorthand for a set of feature flags), a set of additional feature flags, and the - topology (sockets/cores/threads). The libvirt KVM driver provides a number of standard - CPU model names. These models are defined in the file - /usr/share/libvirt/cpu_map.xml. Check this file to determine - which models are supported by your local installation. - There are two Compute configuration options that determine the type of CPU model - exposed to the hypervisor when using KVM, libvirt_cpu_mode and + Specify the CPU model of KVM guests + The Compute service enables you to control the guest CPU + model that is exposed to KVM virtual machines. Use cases + include: + + + To maximize performance of virtual machines by + exposing new host CPU features to the guest + + + To ensure a consistent default CPU across all + machines, removing reliance of variable QEMU + defaults + + + In libvirt, the CPU is specified by providing a base CPU + model name (which is a shorthand for a set of feature + flags), a set of additional feature flags, and the + topology (sockets/cores/threads). The libvirt KVM driver + provides a number of standard CPU model names. These + models are defined in the + /usr/share/libvirt/cpu_map.xml + file. Check this file to determine which models are + supported by your local installation. + Two Compute configuration options define which type of + CPU model is exposed to the hypervisor when using KVM: + libvirt_cpu_mode and libvirt_cpu_model. - The libvirt_cpu_mode option can take one of four values: - none, host-passthrough, - host-model and custom. + The libvirt_cpu_mode option can take + one of the following values: none, + host-passthrough, + host-model, and + custom. Host model (default for KVM & QEMU) - If your nova.conf contains - libvirt_cpu_mode=host-model, libvirt will identify the CPU - model in /usr/share/libvirt/cpu_map.xml which most closely - matches the host, and then request additional CPU flags to complete the match. This - should give close to maximum functionality/performance, which maintaining good - reliability/compatibility if the guest is migrated to another host with slightly - different host CPUs. + If your nova.conf file contains + libvirt_cpu_mode=host-model, + libvirt identifies the CPU model in + /usr/share/libvirt/cpu_map.xml + file that most closely matches the host, and requests + additional CPU flags to complete the match. This + configuration provides the maximum functionality and + performance and maintains good reliability and + compatibility if the guest is migrated to another host + with slightly different host CPUs. - Host passthrough - If your nova.conf contains - libvirt_cpu_mode=host-passthrough, libvirt will tell KVM to - passthrough the host CPU with no modifications. The difference to host-model, - instead of just matching feature flags, every last detail of the host CPU is - matched. This gives absolutely best performance, and can be important to some apps - which check low level CPU details, but it comes at a cost with respect to migration: - the guest can only be migrated to an exactly matching host CPU. + Host pass through + If your nova.conf file contains + libvirt_cpu_mode=host-passthrough, + libvirt tells KVM to pass through the host CPU with no + modifications. The difference to host-model, instead + of just matching feature flags, every last detail of + the host CPU is matched. This gives absolutely best + performance, and can be important to some apps which + check low level CPU details, but it comes at a cost + with respect to migration: the guest can only be + migrated to an exactly matching host CPU. Custom - If your nova.conf file contains libvirt_cpu_mode=custom, you can - explicitly specify one of the supported named model using the libvirt_cpu_model - configuration option. For example, to configure the KVM guests to expose Nehalem - CPUs, your nova.conf should contain: - - libvirt_cpu_mode=custom + If your nova.conf file contains + libvirt_cpu_mode=custom, you + can explicitly specify one of the supported named + model using the libvirt_cpu_model configuration + option. For example, to configure the KVM guests to + expose Nehalem CPUs, your + nova.conf file should + contain: + libvirt_cpu_mode=custom libvirt_cpu_model=Nehalem - - None (default for all libvirt-driven hypervisors other than KVM & - QEMU) - If your nova.conf contains - libvirt_cpu_mode=none, then - libvirt will not specify any CPU model at all. It will - leave it up to the hypervisor to choose the default - model. This setting is equivalent to the Compute - service behavior prior to the Folsom release. - + None (default for all libvirt-driven hypervisors + other than KVM & QEMU) + If your nova.conf file contains + libvirt_cpu_mode=none, libvirt + does not specify a CPU model. Instead, the hypervisor + chooses the default model. This setting is equivalent + to the Compute service behavior prior to the Folsom + release. +
- KVM Performance Tweaks - A recommended resource to help you improve - the performance of KVM is - the VHostNet - kernel module. This module improves network performance. To load the - kernel module, as root: - # modprobe vhost_net + KVM Performance Tweaks + The VHostNet kernel module improves network + performance. To load the kernel module, run the following + command as root: + # modprobe vhost_net
Troubleshooting Trying to launch a new virtual machine instance fails - with the ERROR state, and the following - error appears in - /var/log/nova/nova-compute.loglibvirtError: internal error no supported architecture for os type 'hvm' - This is a symptom that the KVM kernel modules have not - been loaded. + with the ERRORstate, and the following + error appears in the + /var/log/nova/nova-compute.log + file: + libvirtError: internal error no supported architecture for os type 'hvm' + This message indicates that the KVM kernel modules were + not loaded. If you cannot start VMs after installation without - rebooting, it's possible the permissions are not correct. - This can happen if you load the KVM module before you've - installed nova-compute. To check the permissions, run - ls -l /dev/kvm to see whether - the group is set to kvm. If not, run sudo - udevadm trigger. + rebooting, the permissions might not be correct. This can + happen if you load the KVM module before you install + nova-compute. + To check whether the group is set to kvm, run: + # ls -l /dev/kvm + If it is not set to kvm, run: + # sudo udevadm trigger
diff --git a/doc/common/section_kvm_enable.xml b/doc/common/section_kvm_enable.xml new file mode 100644 index 0000000000..c06c75e1a6 --- /dev/null +++ b/doc/common/section_kvm_enable.xml @@ -0,0 +1,101 @@ + +
+ Enabling KVM + To perform the following steps, you must be logged in as + the root user. + + + To determine whether the svm + or vmx CPU extensions are + present, run the following command: + # grep -E 'svm|vmx' /proc/cpuinfo + This command generates output if the CPU is + hardware-virtualization capable. Even if output is + shown, you may still need to enable virtualization + in the system BIOS for full support. + If no output appears, consult your system + documentation to ensure that your CPU and + motherboard support hardware virtualization. + Verify that any relevant hardware virtualization + options are enabled in the system BIOS. + Each manufacturer's BIOS is different. If you need to enable virtualization in + the BIOS, look for an option containing the words "virtualization", "VT", "VMX", or + "SVM." + + + To list the loaded kernel modules and verify + that the kvm modules are + loaded, run the following command: + # lsmod | grep kvm + If the output includes kvm_intel or + kvm_amd, the kvm hardware + virtualization modules are loaded and your kernel meets the module requirements for + OpenStack Compute. + If the output does not show that the kvm module + is loaded, run the following command to load + it: + # modprobe -a kvm + Run the command for your CPU. For Intel, run + this command: + # modprobe -a kvm-intel + For AMD, run this command: + # modprobe -a kvm-amd + Because a KVM installation can change user group + membership, you might need to log in again for + changes to take effect. + If the kernel modules do not load automatically, please use the procedures listed + in the subsections below. + + + This completes the required checks to ensure that + hardware virtualization support is available and enabled, + and that the correct kernel modules are loaded. + If the checks indicate that required hardware + virtualization support or kernel modules are disabled or + not available, you must either enable this support on the + system or find a system with this support. + + Some systems require that you enable VT support in + the system BIOS. If you believe your processor + supports hardware acceleration but the previous + command did not produce output, you might need to + reboot your machine, enter the system BIOS, and enable + the VT option. + + If KVM acceleration is not supported, configure Compute + to use a different hypervisor, such as QEMU or Xen. + The following procedures will help you load the kernel modules for Intel-based and + AMD-based processors if they did not load automatically during KVM installation. +
+ Intel-based processors + If your compute host is Intel-based, run the + following command as root to load the kernel + modules: + # modprobe kvm +# modprobe kvm-intel + Add the following lines to the + /etc/modules file so that + these modules load on reboot: + kvm +kvm-intel +
+
+ AMD-based processors + If your compute host is AMD-based, run the following + command as root to load the kernel modules: + # modprobe kvm +# modprobe kvm-amd + Add the following lines to + /etc/modules file so that + these modules load on reboot: + kvm +kvm-amd +
+
diff --git a/doc/install-guide/section_nova-kvm.xml b/doc/install-guide/section_nova-kvm.xml index e26a78b58e..0816a123a6 100644 --- a/doc/install-guide/section_nova-kvm.xml +++ b/doc/install-guide/section_nova-kvm.xml @@ -4,79 +4,11 @@ version="5.0" xml:id="nova-kvm"> Enabling KVM on the Compute Node - - The OpenStack Compute Service requires hardware virtualization support - and certain kernel modules. Follow this procedure to determine whether - your system has hardware virtualization support and the correct kernel - modules available. In many cases, this is installed for you by your - distribution and you do not need to perform any additional action. - - - All steps listed must be performed while logged into the system as the - root user. - - - - - Use the grep command to check for the - presence of the svm or vmx - CPU extensions by inspecting the /proc/cpuinfo - file generated by the kernel: - - # grep -E 'svm|vmx' /proc/cpuinfo - - If any output is shown after running this command then the CPU - is hardware virtualization capable. Even if output is shown, - you may still need to enable virtualization in the system BIOS - for full support. - - - If output is not shown then consult your - system documentation to ensure that your CPU and motherboard - support hardware virtualization. Verify that any relevant - hardware virtualization options are enabled in the system BIOS. - - - Each manufacturer's BIOS is different. If you need to enable - virtualization in the BIOS, look for an option containing the - words "virtualization", "VT", "VMX", or "SVM". - - - - - Use the lsmod command to list the loaded - kernel modules and verify that the kvm - modules are loaded: - - # lsmod | grep kvm - - If the output includes kvm_intel or - kvm_amd then the kvm - hardware virtualization modules are loaded and your kernel meets - the module requirements for the OpenStack Compute Service. - - If the output does not appear to have the kvm module loaded, - you should be able to load it with: - # modprobe -a kvm - then for your particular CPU, choose either intel: - # modprobe -a kvm-intel - or amd: - # modprobe -a kvm-amd - However, as kvm installation may change the groups your user is - a member of, you may need to re-login for changes to take effect. - - - - - This completes the required checks to ensure hardware virtualization - support is available and enabled, and that you have the correct kernel - modules loaded. - - - If the checks indicated that either hardware virtualization support or - the required kernel modules are not available or not enabled then you - must take action to either find a system that does have the required - hardware virtualization support and modules, or enable it on the system - that failed the checks. - + + OpenStack Compute requires hardware virtualization support and certain kernel modules. To + determine whether your system has hardware virtualization support and the correct kernel + modules available and to enable KVM, use the following procedure. In many cases, this is + installed for you by your distribution and you do not need to perform any additional action. + +