Nova具体功能如下：
1 实例生命周期管理
2 管理计算资源
3 网络和认证管理
4 REST风格的API
5 异步的一致性通信
6 Hypervisor透明：支持Xen,XenServer/XCP, KVM, UML, VMware vSphere and Hyper-V
8.1 部署与配置nova - ALL Compute
#安装kvm&qemu源包
wget http://rpmfind.net/linux/centos/8.2.2004/extras/x86_64/os/Packages/centos-release-gluster6-1.0-1.el8.noarch.rpm
rpm -ivh centos-release-gluster6-1.0-1.el8.noarch.rpm
yum makecache
#安装包
yum install openstack-nova-compute -y
#备份nova配置
cp /etc/nova/nova.conf /etc/nova/nova.conf.bak
egrep -v "^$|^#" /etc/nova/nova.conf.bak >/etc/nova/nova.conf
#配置nova配置文件，在对应项底下增加以下字段
#vim /etc/nova/nova.conf
[DEFAULT]
# ...
my_ip = 172.16.1.163
transport_url = rabbit://rabbitmq:rabbitmq.123@controller160:5672,rabbitmq:rabbitmq.123@controller161:5672,rabbitmq:rabbitmq.123@controller162:5672
[api]
# ...
auth_strategy = keystone
[keystone_authtoken]
# ...
www_authenticate_uri = http://controller168:5000
auth_url = http://controller168:5000
memcached_servers = controller160:11211,controller161:11211,controller162:11211
auth_type = password
project_domain_name = Default
user_domain_name = Default
project_name = service
username = nova
password = nova.123
[vnc]
enabled = true
server_listen = 0.0.0.0
server_proxyclient_address = $my_ip
#因某些未做主机绑定的客户端不能访问”controller168”名字，改为使用具体的ip地址
novncproxy_base_url = http://172.16.1.168:6080/vnc_auto.html
[glance]
# ...
api_servers = http://controller168:9292
[oslo_concurrency]
# ...
lock_path = /var/lib/nova/tmp
[placement]
# ...
region_name = RegionOne
project_domain_name = Default
project_name = service
auth_type = password
user_domain_name = Default
auth_url = http://controller168:5000/v3
username = placement
password = placement.123
[libvirt]
# ...
virt_type = qemu
#根据实际硬件支持填写支持项qemu/kvm
#通过“egrep -c ‘(vmx|svm)’ /proc/cpuinfo”命令查看主机是否支持硬件加速，返回1或者更大的值表示支持，返回0表示不支持；
#支持硬件加速使用”kvm”类型，不支持则使用”qemu”类型；
#一般虚拟机不支持硬件加速
#重启nova服务，并配置开机启动:
systemctl enable libvirtd.service openstack-nova-compute.service
systemctl start libvirtd.service openstack-nova-compute.service
systemctl status libvirtd.service openstack-nova-compute.service
8.2 nova-compute服务验证 - controller160
#加载管理凭证
source adminrc.sh
#查看计算节点列表
openstack compute service list
#输出
[root@controller160 ~]# openstack compute service list
+----+----------------+---------------+----------+---------+-------+----------------------------+
| ID | Binary | Host | Zone | Status | State | Updated At |
+----+----------------+---------------+----------+---------+-------+----------------------------+
| 13 | nova-conductor | controller160 | internal | enabled | up | 2020-06-21T05:16:19.000000 |
| 19 | nova-scheduler | controller160 | internal | enabled | up | 2020-06-21T05:16:20.000000 |
| 20 | nova-conductor | controller162 | internal | enabled | up | 2020-06-21T05:16:16.000000 |
| 23 | nova-scheduler | controller162 | internal | enabled | up | 2020-06-21T05:16:17.000000 |
| 25 | nova-conductor | controller161 | internal | enabled | up | 2020-06-21T05:16:18.000000 |
| 26 | nova-scheduler | controller161 | internal | enabled | up | 2020-06-21T05:16:20.000000 |
| 47 | nova-compute | compute163 | nova | enabled | up | 2020-06-21T05:16:14.000000 |
| 48 | nova-compute | compute164 | nova | enabled | up | 2020-06-21T05:16:17.000000 |
+----+----------------+---------------+----------+---------+-------+----------------------------+
#发现计算节点：
su -s /bin/sh -c "nova-manage cell_v2 discover_hosts --verbose" nova
#输出
[root@controller160 ~]# 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 computes from cell 'cell1': 3c43b8cf-140d-401f-8b1c-4140ddad20a3
Checking host mapping for compute host 'compute163': f4021a77-37d8-4325-84a4-b47b0443aa02
Creating host mapping for compute host 'compute163': f4021a77-37d8-4325-84a4-b47b0443aa02
Checking host mapping for compute host 'compute164': f76880fb-90b7-47fc-8105-68f8f3e08914
Creating host mapping for compute host 'compute164': f76880fb-90b7-47fc-8105-68f8f3e08914
Found 2 unmapped computes in cell: 3c43b8cf-140d-401f-8b1c-4140ddad20a3
#计算节点自动发现配置，在nova.conf添加如下配置
vim /etc/nova/nova.conf
[scheduler]
discover_hosts_in_cells_interval = 300
#执行状态检查，都为success为正常
nova-status upgrade check
#输出
+------------------------------------+
| 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: Cinder API |
| Result: Success |
| Details: None |
+------------------------------------+
| Check: Policy Scope-based Defaults |
| Result: Success |
| Details: None |
+------------------------------------+
至此，nova-compute服务已部署完毕，如有问题请联系我改正，感激不尽！
8.x 部署过程遇到的问题汇总
eg1. 查看节点是否支持硬件加速
egrep -c '(vmx|svm)' /proc/cpuinfo
输出为0时，/etc/nova/nova-compute.conf配置需要更改成以下项
virt_type = qemu
输出为1时，更改成
virt_type = kvm
eg2.Error:
Problem: package openstack-nova-compute-1:21.0.0-1.el8.noarch requires qemu-kvm-core >= 3.1.0, but none of the providers can be installed
- package qemu-kvm-core-15:2.12.0-99.module_el8.2.0+320+13f867d7.x86_64 requires glusterfs-api >= 3.6.0, but none of the providers can be installed
- package qemu-kvm-core-15:4.1.0-23.el8.1.x86_64 requires glusterfs-api >= 3.6.0, but none of the providers can be installed
- package qemu-kvm-core-15:4.2.0-19.el8.x86_64 requires glusterfs-api >= 3.6.0, but none of the providers can be installed
- cannot install the best candidate for the job
- nothing provides glusterfs-libs(x86-64) = 6.0-20.el8 needed by glusterfs-api-6.0-20.el8.x86_64
- nothing provides glusterfs(x86-64) = 6.0-20.el8 needed by glusterfs-api-6.0-20.el8.x86_64
- nothing provides glusterfs-client-xlators(x86-64) = 6.0-20.el8 needed by glusterfs-api-6.0-20.el8.x86_64
(try to add '--skip-broken' to skip uninstallable packages or '--nobest' to use not only best candidate packages)
解决方案：
wget http://rpmfind.net/linux/centos/8.2.2004/extras/x86_64/os/Packages/centos-release-gluster6-1.0-1.el8.noarch.rpm
rpm -ivh centos-release-gluster6-1.0-1.el8.noarch.rpm
yum makecache