Image caches accelerate image pulling and reduce the startup time of elastic container instances. This topic describes how to create, query, update, and delete an image cache.
Create an image cache
You can manually create an image cache by using the Elastic Container Instance console or by calling an API operation in OpenAPI Explorer.
The system can automatically create image caches. You can enable automatic match of image caches when you create an elastic container instance. Then, if no image cache is matched, the system automatically creates an image cache.
Create an image cache by calling an API operation
You can call the CreateImageCache API operation to create an image cache. The following table describes the parameters of the operation. For more information, see CreateImageCache.
Parameter | Type | Example | Description |
RegionId | string | cn-hangzhou | The region ID of the image cache. |
ImageCacheName | string | testcache | The name of the image cache. |
Image.N | array | registry-vpc.cn-hangzhou.aliyuncs.com/eci_open/nginx:1.15.10-perl | Container image N that is used to create the image cache. |
SecurityGroupId | string | sg-uf66jeqopgqa9hdn**** | The ID of the security group. |
VSwitchId | string | vsw-uf6h3rbwbm90urjwa**** | The vSwitch ID. |
ImageCacheSize | integer | 20 | The size of the image cache. Unit: GiB. Default value: 20. |
RetentionDays | integer | 7 | The retention period of the image cache. When the specified retention period elapses, the image cache is deleted. Unit: days. |
AutoMatchImageCache | boolean | false | Specifies whether to enable reuse of image layers. If you enable this feature and the image cache that you want to create and an existing image cache contain duplicate image layers, the system reuses the duplicate image layers to create the new image cache. This accelerates the creation of the image cache. Default value: false. |
Flash | boolean | true | Specifies whether to enable the instant image cache feature. This feature can accelerate the creation of image caches. Default value: false. |
When you create image caches, you can pull images from Container Registry Enterprise Edition instances without using secrets. The following table describes corresponding parameters. For more information, see Pull images from a Container Registry instance without using a secret.
Parameter | Type | Example | Description |
AcrRegistryInfo.N.Domain.N | string | test****-registry.cn-beijing.cr.aliyuncs.com | Domain name N of Container Registry Enterprise Edition instance N. By default, all domain names of instance N are displayed. You can specify specific domain names. Separate multiple domain names with commas (,). |
AcrRegistryInfo.N.InstanceName | string | test**** | The name of Container Registry Enterprise Edition instance N. |
AcrRegistryInfo.N.InstanceId | string | cri-nwj395hgf6f3**** | The ID of Container Registry Enterprise Edition instance N. |
AcrRegistryInfo.N.RegionId | string | cn-beijing | The region ID of Container Registry Enterprise Edition instance N. |
Create an image cache by using the Elastic Container Instance console
In the left-side navigation pane of the Elastic Container Instance console, click Image Cache. On the Image Cache page, click Create Image Cache.
On the page that appears, configure parameters.
Parameter description:
Basic parameters: Configure parameters such as Region and Zone, Network Type, and Security Group to create an intermediate instance.
NoteIf you want to pull images over the Internet and no NAT gateway is configured for the virtual private cloud (VPC), associate an elastic IP address (EIP) with the elastic container instance.
Image Cache: Enter a name for the image cache, select the directory and version number of the image that is used to create the image cache, and configure the size and retention period of the image cache based on your requirements.
Credential: If the image that is used to create the image cache is a private image, enter the address, username, and password of the image repository.
Read and select Elastic Container Instance Terms of Service. Click Create and follow the on-screen instructions to complete the subsequent operations.
Go back to the Image Cache page to view the new image cache.
The creation progress of the image cache is displayed in the Status column. When the status changes to Created, the image cache is created. Click the ID of the image cache to go to the details page. View the basic information and events about the image cache.
Query an image cache
After you create an image cache, you can query the information about the image cache. You can use the image cache if the image cache is in the Created (Ready) state.
You can use one of the following methods to query an image cache:
Call the DescribeImageCaches API operation. For more information, see DescribeImageCaches.
In the Elastic Container Instance console, go to the Image Cache page to view the information about the image cache such as its name and status. You can also click the ID of the image cache to view details such as events about the image cache.
Update an image cache
If an image cache is in the Created (Ready) or UpdateFailed state, you can call the UpdateImageCache API operation to update the image cache, such as updating the container image, retention period, and image repository of the image cache. For more information, see UpdateImageCache.
Delete an image cache
Image caches are snapshots. To retain image caches, you are charged for the snapshots. If you do not specify a retention period for an image cache, we recommend that you delete the image cache when it is no longer needed.
The image caches that are automatically created by the system are managed by Alibaba Cloud. If the image caches are not used within 30 days, they are automatically deleted.
You can use one of the following methods to delete an image cache:
Call the DeleteImageCache API operation. For more information, see DeleteImageCache.
In the Elastic Container Instance console, go to the Image Cache page, select the image cache that you want to delete, and click Delete in the Actions column.