云计算管理平台之OpenStack镜像服务glance
一、glance简介
openstack中的glance服务是用来存储在openstack上启动虚拟机所需镜像；它主要用于发现、注册及检索虚拟机镜像；它通过提供RESTful风格的api对外提供服务；所谓RESTful风格的api指用户可以通过http请求查询虚拟机的镜像元数据以及通过http请求获取镜像文件；其中虚拟机镜像文件的存储可以是本地文件系统，或者对象存储系统（如openstack object storage）或者http，总之存储镜像的系统有很多；其大致的架构如下
glance服务主要有四部分组成，其中glance-api主要提供服务接口，负责接收对image service api中的镜像文件的查看、下载以及存储请求；glance-registry主要用来存储、处理及获取镜像文件中的元数据信息；比如虚拟机镜像文件大小、类型、创建时间、名称等等；glance database主要用来存储虚拟机镜像文件的元数据信息；不同于glace-registry，它不处理元数据信息，而是将glance-registry处理以后的信息保存下来，我们可以理解glance-registry是将虚拟机的镜像元数据信息通过某种格式写入到glance database中进行存储；最后是存放镜像文件的存储仓库；镜像存储仓库就是用来存放真正的镜像文件，它支持多种类型的镜像文件存储机制，包括使用普通的文件系统、对象存储、RADOS块设备、http以及亚马逊的s3等等；
glance工作过程
客户端（通常是openstack中的其他组件，Horizon/nova或者glance专有客户端工具）将请求发送给glance-api，glance-api接收到客户端的请求，它首先会去glance-registry中查询对应的镜像元数据信息，拿到元数据信息后，glance-api会通过返回的元数据信息，用对应的存储适配器连接镜像仓库，进行镜像下载；
二、glance服务的安装、配置、测试
1、创建glance数据库和glance用户，并授权glance用户允许从任何主机连接以及对glance数据库有所有的权限
[root@node02 ~]# mysql
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MariaDB connection id is 11
Server version: 10.1.20-MariaDB MariaDB Server Copyright (c) 2000, 2016, Oracle, MariaDB Corporation Ab and others. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. MariaDB [(none)]> CREATE DATABASE glance;
Query OK, 1 row affected (0.00 sec) MariaDB [(none)]> GRANT ALL PRIVILEGES ON glance.* TO 'glance'@'%' IDENTIFIED BY 'glance123';
Query OK, 0 rows affected (0.00 sec) MariaDB [(none)]> flush privileges;
Query OK, 0 rows affected (0.00 sec) MariaDB [(none)]>
验证：在别的主机上使用glance用户连接数据库，看看是否能够正常连接？
[root@node01 ~]# mysql -uglance -pglance123 -hnode02
Welcome to the MariaDB monitor. Commands end with ; or \g.
Your MariaDB connection id is 12
Server version: 10.1.20-MariaDB MariaDB Server Copyright (c) 2000, 2016, Oracle, MariaDB Corporation Ab and others. Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. MariaDB [(none)]> show databases;
+--------------------+
| Database |
+--------------------+
| glance |
| information_schema |
| test |
+--------------------+
3 rows in set (0.00 sec) MariaDB [(none)]>
2、导出admin用户的环境变量，创建glance用户并设置其密码为glance
[root@node01 ~]# source admin.sh
[root@node01 ~]# openstack user create --domain default --password-prompt glance
User Password:
Repeat User Password:
+---------------------+----------------------------------+
| Field | Value |
+---------------------+----------------------------------+
| domain_id | 47c0915c914c49bb8670703e4315a80f |
| enabled | True |
| id | 11adbc225a88482fb0313b415d2e909f |
| name | glance |
| options | {} |
| password_expires_at | None |
+---------------------+----------------------------------+
[root@node01 ~]#
3、将glance用户授权为admin角色，并将其添加到service项目中
[root@node01 ~]# openstack role add --project service --user glance admin
[root@node01 ~]#
4、创建glance服务
[root@node01 ~]# openstack service create --name glance \
> --description "OpenStack Image" image
+-------------+----------------------------------+
| Field | Value |
+-------------+----------------------------------+
| description | OpenStack Image |
| enabled | True |
| id | a6e98cad2c744ed9b73735a149f1bfe9 |
| name | glance |
| type | image |
+-------------+----------------------------------+
[root@node01 ~]#
5、创建glance endport （服务端点，注册服务）
公共端点
[root@node01 ~]# openstack endpoint create --region RegionOne image public http://controller:9292
+--------------+----------------------------------+
| Field | Value |
+--------------+----------------------------------+
| enabled | True |
| id | 358ccfc245264b60a9d1a0c113dfa628 |
| interface | public |
| region | RegionOne |
| region_id | RegionOne |
| service_id | a6e98cad2c744ed9b73735a149f1bfe9 |
| service_name | glance |
| service_type | image |
| url | http://controller:9292 |
+--------------+----------------------------------+
[root@node01 ~]#
私有端点
[root@node01 ~]# openstack endpoint create --region RegionOne image internal http://controller:9292
+--------------+----------------------------------+
| Field | Value |
+--------------+----------------------------------+
| enabled | True |
| id | 09f5ec434ea24d4c8dc9efe2bbb62b01 |
| interface | internal |
| region | RegionOne |
| region_id | RegionOne |
| service_id | a6e98cad2c744ed9b73735a149f1bfe9 |
| service_name | glance |
| service_type | image |
| url | http://controller:9292 |
+--------------+----------------------------------+
[root@node01 ~]#
管理端点
[root@node01 ~]# openstack endpoint create --region RegionOne image admin http://controller:9292
+--------------+----------------------------------+
| Field | Value |
+--------------+----------------------------------+
| enabled | True |
| id | 04cd3747614b42a3ba086cef39a1acd9 |
| interface | admin |
| region | RegionOne |
| region_id | RegionOne |
| service_id | a6e98cad2c744ed9b73735a149f1bfe9 |
| service_name | glance |
| service_type | image |
| url | http://controller:9292 |
+--------------+----------------------------------+
[root@node01 ~]#
6、安装openstack-glance
[root@node01 ~]# yum install openstack-glance -y
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* base: mirrors.aliyun.com
* centos-qemu-ev: mirrors.aliyun.com
* extras: mirrors.aliyun.com
* updates: mirrors.aliyun.com
Resolving Dependencies
--> Running transaction check
---> Package openstack-glance.noarch 1:17.0.1-1.el7 will be installed
--> Processing Dependency: python-glance = 1:17.0.1-1.el7 for package: 1:openstack-glance-17.0.1-1.el7.noarch
--> Running transaction check
---> Package python-glance.noarch 1:17.0.1-1.el7 will be installed
--> Processing Dependency: python2-glance-store >= 0.26.1 for package: 1:python-glance-17.0.1-1.el7.noarch
--> Processing Dependency: python2-os-brick >= 1.8.0 for package: 1:python-glance-17.0.1-1.el7.noarch
--> Processing Dependency: python2-oslo-vmware >= 0.11.1 for package: 1:python-glance-17.0.1-1.el7.noarch
--> Processing Dependency: python2-swiftclient >= 2.2.0 for package: 1:python-glance-17.0.1-1.el7.noarch
--> Processing Dependency: python2-taskflow >= 2.16.0 for package: 1:python-glance-17.0.1-1.el7.noarch
--> Processing Dependency: python2-wsme >= 0.8 for package: 1:python-glance-17.0.1-1.el7.noarch
--> Processing Dependency: pysendfile for package: 1:python-glance-17.0.1-1.el7.noarch
--> Processing Dependency: python-httplib2 for package: 1:python-glance-17.0.1-1.el7.noarch
--> Processing Dependency: python-retrying for package: 1:python-glance-17.0.1-1.el7.noarch
--> Processing Dependency: python2-boto for package: 1:python-glance-17.0.1-1.el7.noarch
--> Processing Dependency: python2-cursive for package: 1:python-glance-17.0.1-1.el7.noarch
--> Running transaction check
……省略部分内容……
Installed:
openstack-glance.noarch 1:17.0.1-1.el7 Dependency Installed:
atlas.x86_64 0:3.10.1-12.el7 device-mapper-multipath.x86_64 0:0.4.9-131.el7
device-mapper-multipath-libs.x86_64 0:0.4.9-131.el7 libgfortran.x86_64 0:4.8.5-39.el7
libquadmath.x86_64 0:4.8.5-39.el7 libxslt.x86_64 0:1.1.28-5.el7
pysendfile.x86_64 0:2.0.0-5.el7 python-glance.noarch 1:17.0.1-1.el7
python-lxml.x86_64 0:3.2.1-4.el7 python-networkx.noarch 0:1.10-1.el7
python-networkx-core.noarch 0:1.10-1.el7 python-nose.noarch 0:1.3.7-7.el7
python-oslo-privsep-lang.noarch 0:1.29.2-1.el7 python-oslo-vmware-lang.noarch 0:2.31.0-1.el7
python-retrying.noarch 0:1.2.3-4.el7 python-simplegeneric.noarch 0:0.8-7.el7
python2-automaton.noarch 0:1.15.0-1.el7 python2-boto.noarch 0:2.45.0-3.el7
python2-castellan.noarch 0:0.19.0-1.el7 python2-cursive.noarch 0:0.2.2-1.el7
python2-glance-store.noarch 0:0.26.2-1.el7 python2-httplib2.noarch 0:0.18.1-3.el7
python2-numpy.x86_64 1:1.14.5-1.el7 python2-os-brick.noarch 0:2.5.10-1.el7
python2-os-win.noarch 0:4.0.1-1.el7 python2-oslo-privsep.noarch 0:1.29.2-1.el7
python2-oslo-rootwrap.noarch 0:5.14.2-1.el7 python2-oslo-vmware.noarch 0:2.31.0-1.el7
python2-rsa.noarch 0:3.4.2-1.el7 python2-scipy.x86_64 0:0.18.0-3.el7
python2-suds.noarch 0:0.7-0.4.94664ddd46a6.el7 python2-swiftclient.noarch 0:3.6.1-1.el7
python2-taskflow.noarch 0:3.2.0-1.el7 python2-wsme.noarch 0:0.9.3-1.el7
sg3_utils.x86_64 1:1.37-19.el7 sg3_utils-libs.x86_64 1:1.37-19.el7
sysfsutils.x86_64 0:2.1.0-16.el7 Dependency Updated:
kpartx.x86_64 0:0.4.9-131.el7 Complete!
[root@node01 ~]#
7、配置gilance-api
编辑/etc/glance/glance-api.conf文件，在【database】配置段配置连接glance数据的地址
在【keystone_authtoken】配置段中配置认证相关信息
提示：这里需要注意memcached服务的地址；我这里memcached没有在控制节点，而是单独放在了数据库节点上的；
在【paste_deploy】配置段中添加flavor = keystone
在【glance_store】配置段中配置后端存储相关信息
glance-api.conf最终配置
[root@node01 ~]# grep "^[a-Z\[]" /etc/glance/glance-api.conf
[DEFAULT]
[cors]
[database]
connection = mysql+pymysql://glance:glance123@node02/glance
[glance_store]
stores = file,http
default_store = file
filesystem_store_datadir = /var/lib/glance/images/
[image_format]
[keystone_authtoken]
www_authenticate_uri = http://controller:5000
auth_url = http://controller:5000
memcached_servers = node02:11211
auth_type = password
project_domain_name = Default
user_domain_name = Default
project_name = service
username = glance
password = glance
[matchmaker_redis]
[oslo_concurrency]
[oslo_messaging_amqp]
[oslo_messaging_kafka]
[oslo_messaging_notifications]
[oslo_messaging_rabbit]
[oslo_messaging_zmq]
[oslo_middleware]
[oslo_policy]
[paste_deploy]
flavor = keystone
[profiler]
[store_type_location_strategy]
[task]
[taskflow_executor]
[root@node01 ~]#
8、配置glance-registry
编辑/etc/glance/glance-registry.conf，在【database】配置段配置连接glance数据的地址
在【keystone_authtoken】配置段中配置认证相关信息
在【paste_deploy】配置段中添加flavor = keystone
glance-registry.conf的最终配置
[root@node01 ~]# grep "^[a-Z\[]" /etc/glance/glance-registry.conf
[DEFAULT]
[database]
connection = mysql+pymysql://glance:glance123@node02/glance
[keystone_authtoken]
www_authenticate_uri = http://controller:5000
auth_url = http://controller:5000
memcached_servers = node02:11211
auth_type = password
project_domain_name = Default
user_domain_name = Default
project_name = service
username = glance
password = glance
[matchmaker_redis]
[oslo_messaging_amqp]
[oslo_messaging_kafka]
[oslo_messaging_notifications]
[oslo_messaging_rabbit]
[oslo_messaging_zmq]
[oslo_policy]
[paste_deploy]
flavor = keystone
[profiler]
[root@node01 ~]#
9、初始化glance数据，生成相关表
[root@node01 ~]# su -s /bin/sh -c "glance-manage db_sync" glance
/usr/lib/python2.7/site-packages/oslo_db/sqlalchemy/enginefacade.py:1352: OsloDBDeprecationWarning: EngineFacade is deprecated; please use oslo_db.sqlalchemy.enginefacade
expire_on_commit=expire_on_commit, _conf=conf)
INFO [alembic.runtime.migration] Context impl MySQLImpl.
INFO [alembic.runtime.migration] Will assume non-transactional DDL.
INFO [alembic.runtime.migration] Running upgrade -> liberty, liberty initial
INFO [alembic.runtime.migration] Running upgrade liberty -> mitaka01, add index on created_at and updated_at columns of 'images' table
INFO [alembic.runtime.migration] Running upgrade mitaka01 -> mitaka02, update metadef os_nova_server
INFO [alembic.runtime.migration] Running upgrade mitaka02 -> ocata_expand01, add visibility to images
INFO [alembic.runtime.migration] Running upgrade ocata_expand01 -> pike_expand01, empty expand for symmetry with pike_contract01
INFO [alembic.runtime.migration] Running upgrade pike_expand01 -> queens_expand01
INFO [alembic.runtime.migration] Running upgrade queens_expand01 -> rocky_expand01, add os_hidden column to images table
INFO [alembic.runtime.migration] Running upgrade rocky_expand01 -> rocky_expand02, add os_hash_algo and os_hash_value columns to images table
INFO [alembic.runtime.migration] Context impl MySQLImpl.
INFO [alembic.runtime.migration] Will assume non-transactional DDL.
Upgraded database to: rocky_expand02, current revision(s): rocky_expand02
INFO [alembic.runtime.migration] Context impl MySQLImpl.
INFO [alembic.runtime.migration] Will assume non-transactional DDL.
INFO [alembic.runtime.migration] Context impl MySQLImpl.
INFO [alembic.runtime.migration] Will assume non-transactional DDL.
Database migration is up to date. No migration needed.
INFO [alembic.runtime.migration] Context impl MySQLImpl.
INFO [alembic.runtime.migration] Will assume non-transactional DDL.
INFO [alembic.runtime.migration] Context impl MySQLImpl.
INFO [alembic.runtime.migration] Will assume non-transactional DDL.
INFO [alembic.runtime.migration] Running upgrade mitaka02 -> ocata_contract01, remove is_public from images
INFO [alembic.runtime.migration] Running upgrade ocata_contract01 -> pike_contract01, drop glare artifacts tables
INFO [alembic.runtime.migration] Running upgrade pike_contract01 -> queens_contract01
INFO [alembic.runtime.migration] Running upgrade queens_contract01 -> rocky_contract01
INFO [alembic.runtime.migration] Running upgrade rocky_contract01 -> rocky_contract02
INFO [alembic.runtime.migration] Context impl MySQLImpl.
INFO [alembic.runtime.migration] Will assume non-transactional DDL.
Upgraded database to: rocky_contract02, current revision(s): rocky_contract02
INFO [alembic.runtime.migration] Context impl MySQLImpl.
INFO [alembic.runtime.migration] Will assume non-transactional DDL.
Database is synced successfully.
[root@node01 ~]#
验证：去数据库中查看glance库中是否有表生成？
MariaDB [(none)]> use glance;
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A Database changed
MariaDB [glance]> show tables;
+----------------------------------+
| Tables_in_glance |
+----------------------------------+
| alembic_version |
| image_locations |
| image_members |
| image_properties |
| image_tags |
| images |
| metadef_namespace_resource_types |
| metadef_namespaces |
| metadef_objects |
| metadef_properties |
| metadef_resource_types |
| metadef_tags |
| migrate_version |
| task_info |
| tasks |
+----------------------------------+
15 rows in set (0.00 sec) MariaDB [glance]>
10、启动openstack-glance-api和openstack-glance-registry服务，并将其设置为开机启动
[root@node01 ~]# systemctl start openstack-glance-api.service openstack-glance-registry.service
[root@node01 ~]# systemctl enable openstack-glance-api.service openstack-glance-registry.service
Created symlink from /etc/systemd/system/multi-user.target.wants/openstack-glance-api.service to /usr/lib/systemd/system/openstack-glance-api.service.
Created symlink from /etc/systemd/system/multi-user.target.wants/openstack-glance-registry.service to /usr/lib/systemd/system/openstack-glance-registry.service.
[root@node01 ~]# ss -tnl
State Recv-Q Send-Q Local Address:Port Peer Address:Port
LISTEN 0 128 *:9292 *:*
LISTEN 0 128 *:22 *:*
LISTEN 0 100 127.0.0.1:25 *:*
LISTEN 0 128 *:9191 *:*
LISTEN 0 128 :::80 :::*
LISTEN 0 128 :::22 :::*
LISTEN 0 100 ::1:25 :::*
LISTEN 0 128 :::5000 :::*
[root@node01 ~]#
提示：glance-api服务将听在9292端口，glance-registry服务监听在9191端口，确保对应的端口处于监听状态，说明我们的配置没有问题，服务已经正常启动了；
验证：导入admin用户的环境变量，下载一个测试镜像，看看能不能将其上传至glance中去？
[root@node01 ~]# source admin.sh
[root@node01 ~]# rz
rz waiting to receive.
zmodem trl+C ȡ 100% 12418 KB 12418 KB/s 00:00:01 0 Errorsk.img... [root@node01 ~]# ll
total 12428
-rwxr-xr-x 1 root root 272 Oct 28 20:23 admin.sh
-rw-r--r-- 1 root root 12716032 Oct 29 01:10 cirros-0.4.0-x86_64-disk.img
-rwxr-xr-x 1 root root 269 Oct 28 20:24 demo.sh
[root@node01 ~]#
提示：我这里准备了一个cirros的测试镜像；
将cirros上传至glance看看是否能够正常上传？
[root@node01 ~]# openstack image create "cirros" \
> --file cirros-0.4.0-x86_64-disk.img \
> --disk-format qcow2 --container-format bare \
> --public
+------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Field | Value |
+------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| checksum | 443b7623e27ecf03dc9e01ee93f67afe |
| container_format | bare |
| created_at | 2020-10-28T17:12:58Z |
| disk_format | qcow2 |
| file | /v2/images/94dd2ba0-1736-4307-865d-7cb86b85d32e/file |
| id | 94dd2ba0-1736-4307-865d-7cb86b85d32e |
| min_disk | 0 |
| min_ram | 0 |
| name | cirros |
| owner | b4e56eeb160948c581e98d685133d19a |
| properties | os_hash_algo='sha512', os_hash_value='6513f21e44aa3da349f248188a44bc304a3653a04122d8fb4535423c8e1d14cd6a153f735bb0982e2161b5b5186106570c17a9e58b64dd39390617cd5a350f78', os_hidden='False' |
| protected | False |
| schema | /v2/schemas/image |
| size | 12716032 |
| status | active |
| tags | |
| updated_at | 2020-10-28T17:12:58Z |
| virtual_size | None |
| visibility | public |
+------------------+--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
[root@node01 ~]# openstack image list
+--------------------------------------+--------+--------+
| ID | Name | Status |
+--------------------------------------+--------+--------+
| 94dd2ba0-1736-4307-865d-7cb86b85d32e | cirros | active |
+--------------------------------------+--------+--------+
[root@node01 ~]#
提示：可以看到我们上传到镜像已经在镜像列表中能够看到，说明镜像已经成功上传到glance中去了；
验证：查看glance的镜像仓库目录下是否有文件生成？
[root@node01 ~]# ll /var/lib/glance/images/
total 12420
-rw-r----- 1 glance glance 12716032 Oct 29 01:12 94dd2ba0-1736-4307-865d-7cb86b85d32e
[root@node01 ~]# file /var/lib/glance/images/94dd2ba0-1736-4307-865d-7cb86b85d32e
/var/lib/glance/images/94dd2ba0-1736-4307-865d-7cb86b85d32e: QEMU QCOW Image (v3), 46137344 bytes
[root@node01 ~]#
提示：可以看到在对应的目录下有一个文件生成，其文件格式为qcow image的文件；到此openstack的镜像服务glance的安装配置和测试就完成了；
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