Openstack 使用Centos官方镜像创建实例记录
准备centos镜像
官方地址：http://cloud.centos.org/centos/7/images
可以看到有各种版本的镜像，我在此处下载的是
https://cloud.centos.org/centos/7/images/CentOS-7-x86_64-GenericCloud-1907.raw.tar.gz
其实应该下载https://cloud.centos.org/centos/7/images/CentOS-7-x86_64-GenericCloud-1907.qcow2
后面我将raw格式的镜像又转化为了qcow2格式，因为openstack只支持qcow2格式的镜像。
转化也比较方便，转换方式如下：
#首先解压，压缩后的镜像比较小，下载也比较快
$ tar -zxvf CentOS-7-x86_64-GenericCloud-1907.raw.tar.gz
#转化镜像格式，raw格式转化为qcow2格式
$ qemu-img convert -f raw -O qcow2 CentOS-7-x86_64-GenericCloud-1907.raw CentOS-7-x86_64-GenericCloud-1907.qcow2
$ ls
CentOS-7-x86_64-GenericCloud-1907.qcow2
上传镜像到OpenStack
$ openstack image create "centos-7" --file CentOS-7-x86_64-GenericCloud-1907.qcow2 --disk-format qcow2 --container-format bare --public
# 上传成功后即可查看到已存在镜像列表中
$ openstack image list
+--------------------------------------+---------------------------------+--------+
| ID | Name | Status |
+--------------------------------------+---------------------------------+--------+
| eeff6c96-3255-451b-bd26-8368ac701bae | Centos-7 | active |
| 62903720-0c33-4238-b2fc-106167b3b240 | debian-8.11.0 | active |
| aeae3608-ded5-45af-aca3-bb96df1b3320 | openSUSE | active |
| 721becd1-b2bf-4674-b5d1-7be9e7a9c263 | ubuntu-16.04-x86_64 | active |
+--------------------------------------+---------------------------------+--------+
用新镜像创建实例
首先需要准备创建镜像所需要的条件，例如 实例类型、网络、秘钥等等，由于我之前已经创建过了，此处就直接拿来用即可，新环境需要去创建这些东西，此处不赘述。
此处用命令行去创建实例，也可在页面上去创建实例。
# 查看已创建好的实例类型
$ openstack flavor list
+--------------------------------------+-----------------+-------+------+-----------+-------+-----------+
| ID | Name | RAM | Disk | Ephemeral | VCPUs | Is Public |
+--------------------------------------+-----------------+-------+------+-----------+-------+-----------+
| 0bd4ccb3-7fdb-493a-a7b4-1be94dee1cd5 | 4core_8G_100GB | 8192 | 100 | 0 | 4 | True |
| 2cf9cf3a-14eb-48ac-bbff-a930aeadca10 | 8core_16G_100G | 16384 | 100 | 0 | 8 | True |
| 8d14ecaa-6920-4d68-a69e-9f6e7a4a244c | 2core_4G_50G | 4096 | 50 | 0 | 2 | True |
+--------------------------------------+-----------------+-------+------+-----------+-------+-----------+
# 查看镜像列表
$ openstack image list
+--------------------------------------+---------------------------------+--------+
| ID | Name | Status |
+--------------------------------------+---------------------------------+--------+
| eeff6c96-3255-451b-bd26-8368ac701bae | Centos-7 | active |
| 62903720-0c33-4238-b2fc-106167b3b240 | debian-8.11.0 | active |
| aeae3608-ded5-45af-aca3-bb96df1b3320 | openSUSE | active |
| 721becd1-b2bf-4674-b5d1-7be9e7a9c263 | ubuntu-16.04-x86_64 | active |
+--------------------------------------+---------------------------------+--------+
# 查看网络
$ openstack network list
+--------------------------------------+----------+--------------------------------------+
| ID | Name | Subnets |
+--------------------------------------+----------+--------------------------------------+
| 24ab4664-3d97-4ec8-99fb-75ba5f92fa77 | public | 0507ad6b-153a-4713-93ee-e274d37ce3fa |
| 610c4193-5dff-419c-8df8-442cf8c49bba | provider | 3d59f5f5-2b85-4cb5-b738-a6003aa29bd9 |
| 6ba8cae0-b544-47e3-bcec-da0c8737da74 | private | 29b1a65a-acb2-4e18-af2f-a00083a1c50e |
+--------------------------------------+----------+--------------------------------------+
# 查看秘钥对
$ openstack keypair list
+----------------+-------------------------------------------------+
| Name | Fingerprint |
+----------------+-------------------------------------------------+
| xiaoming | 5a:d2:8f:2f:40:c2:84:1e:95:7a:23:aa:3e:af:aa:10 |
| xiaohong | 00:4c:7e:7c:6e:29:51:cf:af:71:c3:ec:2c:90:83:ea |
+----------------+-------------------------------------------------+
利用以上信息创建实例
$ openstack server create --flavor 4core_8G_100GB --image Centos-7 --nic net-id=610c4193-5dff-419c-8df8-442cf8c49bba --security-group default --key-name xiaoming centos7-test
+-------------------------------------+------------------------------------------------+
| Field | Value |
+-------------------------------------+------------------------------------------------+
| OS-DCF:diskConfig | MANUAL |
| OS-EXT-AZ:availability_zone | |
| OS-EXT-SRV-ATTR:host | None |
| OS-EXT-SRV-ATTR:hypervisor_hostname | None |
| OS-EXT-SRV-ATTR:instance_name | |
| OS-EXT-STS:power_state | NOSTATE |
| OS-EXT-STS:task_state | scheduling |
| OS-EXT-STS:vm_state | building |
| OS-SRV-USG:launched_at | None |
| OS-SRV-USG:terminated_at | None |
| accessIPv4 | |
| accessIPv6 | |
| addresses | |
| adminPass | Lg4mubYrHX2U |
| config_drive | |
| created | 2019-08-14T07:06:18Z |
| flavor | 4core_8G_100GB (0bd4ccb3-7fdb-493a- |
| | a7b4-1be94dee1cd5) |
| hostId | |
| id | aeb3da93-d492-45ee-9f16-7e5a8327fcdf |
| image | CentOS7-image (eeff6c96-3255-451b- |
| | bd26-8368ac701bae) |
| key_name | xiaoming |
| name | centos7-test |
| progress | 0 |
| project_id | 08fe311820f24af489ffce1112f45769 |
| properties | |
| security_groups | name='default' |
| status | BUILD |
| updated | 2019-08-14T07:06:19Z |
| user_id | d518cc05787b49aa8c8f6759c0747aeb |
| volumes_attached | |
+-------------------------------------+------------------------------------------------+
此时，实例已经创建成功，并且已经将xiaoming的公钥注入到该实例中，此时可以ssh到该实例上使用啦。