Install and configure a compute node¶

This section describes how to install and configure the Compute service on a compute node. The service supports several hypervisors to deploy instances or VMs. For simplicity, this configuration uses the QEMU hypervisor with the KVM extension on compute nodes that support hardware acceleration for virtual machines. On legacy hardware, this configuration uses the generic QEMU hypervisor. You can follow these instructions with minor modifications to horizontally scale your environment with additional compute nodes.

Poznámka

This section assumes that you are following the instructions in this guide step-by-step to configure the first compute node. If you want to configure additional compute nodes, prepare them in a similar fashion to the first compute node in the example architectures section. Each additional compute node requires a unique IP address.

Instalace a nastavení součástí¶

Poznámka

Default configuration files vary by distribution. You might need to add these sections and options rather than modifying existing sections and options. Also, an ellipsis (...) in the configuration snippets indicates potential default configuration options that you should retain.

Nainstalujte balíčky:

# zypper install openstack-nova-compute genisoimage qemu-kvm libvirt

Upravte soubor /etc/nova/nova.conf a proveďte následující úkony:
- In the [DEFAULT] section, enable only the compute and metadata APIs:
```
[DEFAULT]
...
enabled_apis = osapi_compute,metadata
```
- In the [DEFAULT] section, set the compute_driver:
```
[DEFAULT]
# ...
compute_driver = libvirt.LibvirtDriver
```
- In the [DEFAULT] section, configure RabbitMQ message queue access:
```
[DEFAULT]
...
transport_url = rabbit://openstack:RABBIT_PASS@controller
```
  Nahraďte RABBIT_PASS Vámi zvoleným heslem pro účet openstack v RabbitMQ.
- V částech [DEFAULT] a [keystone_authtoken] nastavte přístup ke službě identit:
```
[DEFAULT]
...
auth_strategy = keystone

[keystone_authtoken]
...
auth_uri = http://controller:5000
auth_url = http://controller:35357
memcached_servers = controller:11211
auth_type = password
project_domain_name = Default
user_domain_name = Default
project_name = service
username = nova
password = NOVA_PASS
```
  Nahraďte NOVA_PASS vámi zvoleným heslem pro uživatele nova ve službě identit.
  
  Poznámka
  
  Okomentujte nebo odstraňte všechny ostatní možnosti v části [keystone_authtoken].
- V části [DEFAULT] nastavte volbu my_ip:
```
[DEFAULT]
...
my_ip = MANAGEMENT_INTERFACE_IP_ADDRESS
```
  Replace MANAGEMENT_INTERFACE_IP_ADDRESS with the IP address of the management network interface on your compute node, typically 10.0.0.31 for the first node in the example architecture.
- In the [DEFAULT] section, enable support for the Networking service:
```
[DEFAULT]
...
use_neutron = True
firewall_driver = nova.virt.firewall.NoopFirewallDriver
```
  Poznámka
  
  By default, Compute uses an internal firewall service. Since Networking includes a firewall service, you must disable the Compute firewall service by using the nova.virt.firewall.NoopFirewallDriver firewall driver.
- In the [vnc] section, enable and configure remote console access:
```
[vnc]
...
enabled = True
vncserver_listen = 0.0.0.0
vncserver_proxyclient_address = $my_ip
novncproxy_base_url = http://controller:6080/vnc_auto.html
```
  The server component listens on all IP addresses and the proxy component only listens on the management interface IP address of the compute node. The base URL indicates the location where you can use a web browser to access remote consoles of instances on this compute node.
  
  Poznámka
  
  If the web browser to access remote consoles resides on a host that cannot resolve the controller hostname, you must replace controller with the management interface IP address of the controller node.
- In the [glance] section, configure the location of the Image service API:
```
[glance]
...
api_servers = http://controller:9292
```
- V části [oslo_concurrencyservice_credentials] nastavte cestu pro zámky:
```
[oslo_concurrency]
...
lock_path = /var/run/nova
```

Ensure the kernel module nbd is loaded.
```
# modprobe nbd
```
Ensure the module loads on every boot by adding nbd to the /etc/modules-load.d/nbd.conf file.

Dokončení instalace¶

Determine whether your compute node supports hardware acceleration for virtual machines:
```
$ egrep -c '(vmx|svm)' /proc/cpuinfo
```
If this command returns a value of one or greater, your compute node supports hardware acceleration which typically requires no additional configuration.

If this command returns a value of zero, your compute node does not support hardware acceleration and you must configure libvirt to use QEMU instead of KVM.
- Edit the [libvirt] section in the /etc/nova/nova.conf file as follows:
```
[libvirt]
...
virt_type = qemu
```

Start the Compute service including its dependencies and configure them to start automatically when the system boots:

# systemctl enable libvirtd.service openstack-nova-compute.service
# systemctl start libvirtd.service openstack-nova-compute.service

Poznámka

If the nova-compute service fails to start, check /var/log/nova/nova-compute.log. The error message AMQP server on controller:5672 is unreachable likely indicates that the firewall on the controller node is preventing access to port 5672.