~> **Note:** The builder doesn't support Windows images for now and only supports CentOS and Ubuntu images via SSH authentication with `ssh_username` (Required) and `ssh_password` (Optional). The `ssh_username` must be `root` for CentOS images and `ubuntu` for Ubuntu images. The `ssh_password` may contain 8-30 characters, and must consist of at least 2 items out of the capital letters, lower case letters, numbers and special characters. The special characters include `()~!@#\$%^&\*-+=\_|{}\[]:;'<>,.?/`.
- `public_key` - (string) This is the UCloud public key. It must be provided, but it can also be sourced from the `UCLOUD_PUBLIC_KEY` environment variable.
- `private_key` - (string) This is the UCloud private key. It must be provided, but it can also be sourced from the `UCLOUD_PRIVATE_KEY` environment variable.
- `project_id` - (string) This is the UCloud project id. It must be provided, but it can also be sourced from the `UCLOUD_PROJECT_ID` environment variables.
- `region` - (string) This is the UCloud region. It must be provided, but it can also be sourced from the `UCLOUD_REGION` environment variables.
- `availability_zone` - (string) This is the UCloud availability zone where UHost instance is located. such as: `cn-bj2-02`. You may refer to [list of availability_zone](https://docs.ucloud.cn/api/summary/regionlist)
- `instance_type` - (string) The type of UHost instance. You may refer to [list of instance type](https://docs.ucloud.cn/compute/terraform/specification/instance)
- `image_name` - (string) The name of the user-defined image, which contains 1-63 characters and only support Chinese, English, numbers, '-\_,.:[]'.
- `source_image_id` (string) - This is the ID of base image which you want to create your customized images with.
### Optional:
- `base_url` - (string) This is the base url. (Default: `https://api.ucloud.cn`).
- `use_ssh_private_ip` - (boolean) - If this value is true, packer will connect to the created UHost instance via a private ip instead of allocating an EIP (elastic public ip).(Default: `false`).
~> **Note:** By default (`use_ssh_private_ip` is `false`), the launched uhost instance will be connecting with extranet by bounding with an EIP (elastic public ip) automatically, which bandwidth is 30 Mb by default and paid by traffic.
- `vpc_id` - (string) The ID of VPC linked to the UHost instance. If not defined `vpc_id`, the instance will use the default VPC in the current region.
- `subnet_id` - (string) The ID of subnet under the VPC. If `vpc_id` is defined, the `subnet_id` is mandatory required. If `vpc_id` and `subnet_id` are not defined, the instance will use the default subnet in the current region.
- `security_group_id` - (string) The ID of the fire wall associated to UHost instance. If `security_group_id` is not defined,
the instance will use the non-recommended web fire wall, and open port include 22, 3389 by default. It is supported by ICMP fire wall protocols.
- `image_copy_to_mappings` (array of copied image mappings) - The array of mappings regarding the copied images to the destination regions and projects.
- `project_id` (string) - The destination project id, where copying image in.
- `region` (string) - The destination region, where copying image in.
- `name` (string) - The copied image name. If not defined, builder will use `image_name` as default name.
- `description` (number) - The copied image description.
- `wait_image_ready_timeout` (int)Timeout of creating image or copying image. The default timeout is 3600 seconds if this option is not set or is set to 0.
## Examples
Here is a basic example for build UCloud CentOS image:
