Install and configure components

1. Install the packages:

   # yum install openstack-nova-compute

2. Edit the /etc/nova/nova.conf file and complete the following actions:

   ○ In the [DEFAULT] section, enable only the compute and metadata APIs:
       [DEFAULT]
       # ...
       enabled_apis = osapi_compute,metadata
   
   ○ In the [DEFAULT] section, configure RabbitMQ message queue access:
       [DEFAULT]
       # …
       transport_url=rabbit://openstack:openstack123@dbs.flex.net
   
   ○ In the [api] and [keystone_authtoken] sections, configure Identity service access::
       [api]
       # ...
       auth_strategy = keystone
   
       [keystone_authtoken]
       # ...
       auth_url = http://stack.flex.net:5000/v3
       memcached_servers = dbs.flex.net:11211
       auth_type = password
       project_domain_name = Default
       user_domain_name = Default
       project_name = service
       username = nova
       password = nova123
       注意: 注释或移除在掉在[keystone_authtoken]区域中的其它的选项
   
   ○ In the [DEFAULT] section, configure the my_ip option:
       [DEFAULT]
       # ...
       my_ip = 192.168.205.187
   注意：使用管理接口的IP在你的计算节点上.
   
   ○ In the [DEFAULT] section, enable support for the Networking service:
       [DEFAULT]
       # ...
       use_neutron = true
       firewall_driver = nova.virt.firewall.NoopFirewallDriver
   注意：缺省的，计算节点使用一内部的防火墙驱动，因为网络服务包含了一个防火墙驱动，你必须禁用防火墙驱动并使用nova.virt.firewall.NoopFirewallDriver firewall driver
   
   ○ In the [vnc] section, enable and configure remote console access:
       [vnc]
       # ...
       enabled = true
       server_listen = 0.0.0.0
       server_proxyclient_address = $my_ip
       novncproxy_base_url = http://stack.flex.net:6080/vnc_auto.html
   
       服务器组件监听所有IP地址，代理组件只监听计算节点的管理接口IP地址。基本URL指示可以使用web浏览器访问此计算节点上实例的远程控制台的位置。
   注意：如果要访问远程控制台的web浏览器驻留在无法解析控制器主机名的主机上，则必须使用控制器节点的管理接口IP地址替换控制器。
   
   ○ In the [glance] section, configure the location of the Image service API:
       [glance]
       # ...
       api_servers = http://stack.flex.net:9292
   
   ○ In the [oslo_concurrency] section, configure the lock path:
       [oslo_concurrency]
       # ...
       lock_path = /var/lib/nova/tmp
   
   ○ In the [placement] section, configure the Placement API:
       [placement]
       # ...
       region_name = RegionOne
       project_domain_name = Default
       project_name = service
       auth_type = password
       user_domain_name = Default
       auth_url = http://stack.flex.net:5000/v3
       username = placement
       password = placement123

   Finalize installation

3. Determine whether your compute node supports hardware acceleration for virtual machines:

   $ egrep -c '(vmx|svm)' /proc/cpuinfo
   
   如果这个命令返回1或大于1的值，你的计算节点支持硬件加速，通常不需要额外的配置，通常如果你的计算节点使用的是Vmware Workstation虚拟机，你可以充许virtuallze Intel VT-x/EPT or AMD-V/RVI这样打开虚拟化设置
   
   如果这个命令返回一个0值，你的计算节点不支持硬件加速，并且你必须配置libvirt使用QEMU取代KVM, 编辑文件/etc/nova/nova.conf文件如下：
   [libvirt]
   # ...
   virt_type = qemu

4. 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
   
   注意:如果nova-compute服务无法启动，请检查/var/log/nova/nova- computer .log。controller:5672上的错误消息AMQP服务器不可访问，这可能表明控制器节点上的防火墙正在阻止对端口5672的访问。将防火墙配置为打开控制器节点上的端口5672并在计算节点上重新启动nova-compute服务。

   Add the compute node to the cell database

5. Source the admin credentials to enable admin-only CLI commands, then confirm there are compute hosts in the database:

   $ . admin-openrc
   
   $ openstack compute service list --service nova-compute
   +----+-------+--------------+------+-------+---------+----------------------------+
   | ID | Host  | Binary       | Zone | State | Status  | Updated At                 |
   +----+-------+--------------+------+-------+---------+----------------------------+
   | 1  | node1 | nova-compute | nova | up    | enabled | 2017-04-14T15:30:44.000000 |
   +----+-------+--------------+------+-------+---------+----------------------------+

6. Discover compute hosts:

   # su -s /bin/sh -c "nova-manage cell_v2 discover_hosts --verbose" nova
   
   Found 2 cell mappings.
   Skipping cell0 since it does not contain hosts.
   Getting compute nodes from cell 'cell1': ad5a5985-a719-4567-98d8-8d148aaae4bc
   Found 1 computes in cell: ad5a5985-a719-4567-98d8-8d148aaae4bc
   Checking host mapping for compute host 'compute': fe58ddc1-1d65-4f87-9456-bc040dc106b3
   Creating host mapping for compute host 'compute': fe58ddc1-1d65-4f87-9456-bc040dc106b3
   注意：当你添加新的计算节点，你必须运行nova-manage cell_v2 discover_hosts在控制器上注册新的计算节点，替代方法为你可以在/etc/nova/nova.conf中设置一个适当的间间隔自动发现计算节点:
   [scheduler]
   discover_hosts_in_cells_interval = 300

   Verify operation

   Verify operation of the Compute service.
   Note: Perform these commands on the controller node.

7. Source the admin credentials to gain access to admin-only CLI commands:

   $ . admin-openrc

8. List service components to verify successful launch and registration of each process:

   $ openstack compute service list
   
   +----+--------------------+------------+----------+---------+-------+----------------------------+
   | Id | Binary             | Host       | Zone     | Status  | State | Updated At                 |
   +----+--------------------+------------+----------+---------+-------+----------------------------+
   |  1 | nova-scheduler     | controller | internal | enabled | up    | 2016-02-09T23:11:15.000000 |
   |  2 | nova-conductor     | controller | internal | enabled | up    | 2016-02-09T23:11:16.000000 |
   |  3 | nova-compute       | compute1   | nova     | enabled | up    | 2016-02-09T23:11:20.000000 |
   +----+--------------------+------------+----------+---------+-------+----------------------------+
   
   Note: This output should indicate two service components enabled on the controller node and one service component enabled on the compute node.

9. List API endpoints in the Identity service to verify connectivity with the Identity service:

   $ openstack catalog list
   +-----------+-----------+---------------------------------------------+
   | Name      | Type      | Endpoints                                   |
   +-----------+-----------+---------------------------------------------+
   | placement | placement | RegionOne                                   |
   |           |           |   admin: http://stack.flex.net:8778         |
   |           |           | RegionOne                                   |
   |           |           |   internal: http://stack.flex.net:8778      |
   |           |           | RegionOne                                   |
   |           |           |   public: http://stack.flex.net:8778        |
   |           |           |                                             |
   | glance    | image     | RegionOne                                   |
   |           |           |   admin: http://stack.flex.net:9292         |
   |           |           | RegionOne                                   |
   |           |           |   public: http://stack.flex.net:9292        |
   |           |           | RegionOne                                   |
   |           |           |   internal: http://stack.flex.net:9292      |
   |           |           |                                             |
   | nova      | compute   | RegionOne                                   |
   |           |           |   public: http://stack.flex.net:8774/v2.1   |
   |           |           | RegionOne                                   |
   |           |           |   internal: http://stack.flex.net:8774/v2.1 |
   |           |           | RegionOne                                   |
   |           |           |   admin: http://stack.flex.net:8774/v2.1    |
   |           |           |                                             |
   | keystone  | identity  | RegionOne                                   |
   |           |           |   public: http://stack.flex.net:5000/v3/    |
   |           |           | RegionOne                                   |
   |           |           |   admin: http://stack.flex.net:5000/v3/     |
   |           |           | RegionOne                                   |
   |           |           |   internal: http://stack.flex.net:5000/v3/  |
   |           |           |                                             |
   +-----------+-----------+---------------------------------------------+

10. List images in the Image service to verify connectivity with the Image service:

    $ openstack image list
    
    +--------------------------------------+-------------+-------------+
    | ID                                   | Name        | Status      |
    +--------------------------------------+-------------+-------------+
    | 9a76d9f9-9620-4f2e-8c69-6c5691fae163 | cirros      | active      |
    +--------------------------------------+-------------+-------------+

11. Check the cells and placement API are working successfully and that other necessary prerequisites are in place:

    # nova-status upgrade check
    
    +--------------------------------------------------------------------+
    | Upgrade Check Results                                              |
    +--------------------------------------------------------------------+
    | Check: Cells v2                                                    |
    | Result: Success                                                    |
    | Details: None                                                      |
    +--------------------------------------------------------------------+
    | Check: Placement API                                               |
    | Result: Success                                                    |
    | Details: None                                                      |
    +--------------------------------------------------------------------+
    | Check: Ironic Flavor Migration                                     |
    | Result: Success                                                    |
    | Details: None                                                      |
    +--------------------------------------------------------------------+
    | Check: Request Spec Migration                                      |
    | Result: Success                                                    |
    | Details: None                                                      |
    +--------------------------------------------------------------------+
    | Check: Console Auths                                               |
    | Result: Success                                                    |
    | Details: None                                                      |
    +--------------------------------------------------------------------+