Connecting to Container Registry from Virtual Private Cloud

Written by

Updated at November 20, 2024

Prepare your cloud
- Required paid resources
- Required quotas
Configure the CLI profile
Prepare the environment
- Install the required utilities
Deploy your resources
Test the solution
Tips for deployment in the production environment
Delete the resources you created

To work with Container Registry, cloud resources require internet access. Follow this guide to deploy a cloud infrastructure in Yandex Cloud to set up access to Container Registry for resources that are hosted in the Virtual Private Cloud cloud network and have no public IP addresses or access to the internet through a NAT gateway.

Container Registry uses Object Storage to store Docker images in a registry. This solution also has access to Object Storage for resources in Virtual Private Cloud.

After the solution is deployed in Yandex Cloud, the following resources will be created:

Name	Description
`cr-vpc` `*`	Cloud network with the resources for which access to Container Registry is set up.
`cr-nlb`	Internal network load balancer accepts traffic to Container Registry. The load balancer accepts TCP traffic with destination port 443 and distributes it across resources (VMs) in a target group.
`nat-group`	Load balancer target group with VMs that have the NAT function enabled.
`s3-nlb`	Internal network load balancer accepts traffic to Object Storage. The load balancer accepts TCP traffic with destination port 443 and distributes it across resources (VMs) in a target group.
`nat-a1-vm`, `nat-b1-vm`	VMs with NAT in the `ru-central1-a` and `ru-central1-b` zones for routing traffic to Container Registry and Object Storage with translation of IP addresses of traffic sources and targets, as well as for routing the return traffic.
`pub-ip-a1`, `pub-ip-b1`	VM public IP addresses to which the VPC cloud network translates their internal IP addresses.
`DNS zones and A records`	The `storage.yandexcloud.net.` and `cr.yandex.` internal DNS zones in the `cr-vpc` network with `A` resource records mapping domain names to IP addresses of internal network load balancers.
`test-registry`	Registry in Container Registry.
`container-registry-<registry_ID>`	Bucket name in Object Storage for storing Docker images, where `<registry_ID>` is the registry ID. Container Registry automatically creates a bucket for the registry in Object Storage.
`cr-subnet-a`, `cr-subnet-b`	Cloud subnets to host NAT instances in the `ru-central1-a` and `ru-central1-b` zones.
`test-cr-vm`	Test VM to verify access to Container Registry.
`test-cr-subnet-a`	Cloud subnet to host the test VM.

* When deploying, you can also specify an existing cloud network.

Internal DNS zones are created for the cloud network with hosted resources in Cloud DNS:

cr.yandex. and an A resource record that maps the cr.yandex domain name of Container Registry to the IP address of the cr-nlb internal network load balancer.
storage.yandexcloud.net. and an A resource record that maps the storage.yandexcloud.net domain name of Object Storage to the IP address of the s3-nlb internal network load balancer.

With these records, traffic from cloud resources to Container Registry and Object Storage will be routed to internal load balancers that will distribute the load across the NAT instances.

To deploy a NAT instance, an image from Marketplace is used that translates the source and target IP addresses to ensure traffic routing to the Container Registry and Object Storage public IP addresses.

By placing the NAT instances in multiple availability zones, you can ensure fault-tolerant access to Container Registry. By increasing the number of NAT instances, you can scale the solution up if the workload increases. When calculating the number of NAT instances, consider the locality of traffic handling by the internal load balancer.

Only the cloud resources that use this solution can access the registry. The registry access policy allows registry actions only from public IP addresses of NAT instances. You cannot access the registry from other IP addresses. You can disable this limitation by specifying a parameter in Terraform, if required.

For more information, see the project repository.

To deploy a cloud infrastructure to provide access to Container Registry for resources located in the VPC cloud network:

If you no longer need the resources you created, delete them.

Prepare your cloud

Go to the management console and log in to Yandex Cloud or create an account if you do not have one yet.
On the Yandex Cloud Billing page, make sure you have a billing account linked and it has the ACTIVE or TRIAL_ACTIVE status. If you do not have a billing account, create one.

If you have an active billing account, you can go to the cloud page to create or select a folder for your infrastructure to operate in.

Learn more about clouds and folders.

Required paid resources

The infrastructure support cost includes:

Fee for continuously running VMs (see Yandex Compute Cloud pricing).
Fee for using Network Load Balancer (see Yandex Network Load Balancer pricing).
Fee for storing pushed Docker images (see Container Registry pricing).
Fee for using public IP addresses and outgoing traffic (see Yandex Virtual Private Cloud pricing).

Required quotas

Make sure your cloud has sufficient quotas not being used by resources for other jobs.

Number of occupied resources created in the scenario

Resource	Amount
Virtual machines	3
VM instance vCPUs	6
VM instance RAM	6 GB
Disks	3
HDD size	30 GB
SSD size	20 GB
Network load balancer	2
Target group for the load balancer	1
Networks	1`*`
Subnets	3
Static public IP addresses	2
Security groups	1
DNS zone	2
Registry	1
Service accounts	1

* If you do not specify the ID of an existing network in terraform.tfvars.

Configure the CLI profile

If you do not have the Yandex Cloud command line interface yet, install it and sign in as a user.
Create a service account:
Management console

CLI

API
1. In the management console, select the folder where you want to create a service account.
2. In the list of services, select Identity and Access Management.
3. Click Create service account.
4. Enter a name for the service account, e.g., sa-terraform.
5. Click Create.
The folder specified in the CLI profile is used by default. You can specify a different folder using the --folder-name or --folder-id parameter.

Run the command below to create a service account, specifying the sa-terraform name:
```
yc iam service-account create --name sa-terraform
```
Where name is the service account name.

Result:
```
id: ajehr0to1g8b********
folder_id: b1gv87ssvu49********
created_at: "2023-06-20T09:03:11.665153755Z"
name: sa-terraform
```
To create a service account, use the ServiceAccountService/Create gRPC API call or the create REST API method for the ServiceAccount resource.
Assign the service account the administrator role for the folder:
Management console

CLI

API
1. In the management console, select the folder where the service account is located.
2. Go to the Access bindings tab.
3. Select sa-terraform from the account list and click -> Edit roles.
4. Click Add role in the dialog that opens and select the admin role.
Run this command:
```
yc resource-manager folder add-access-binding <folder_ID> \
   --role admin \
   --subject serviceAccount:<service_account_ID>
```
To assign the service account a role for the folder, use the setAccessBindings REST API method for the ServiceAccount resource or the ServiceAccountService/SetAccessBindings gRPC API call.
Set up the CLI profile to run operations on behalf of the service account:
CLI
1. Create an authorized key for the service account and save it to the file:
  yc iam key create \ --service-account-id <service_account_ID> \ --folder-id <ID_of_folder_with_service_account> \ --output key.json
  Where:
  - service-account-id: Service account ID.
  - folder-id: ID of the folder in which the service account was created.
  - output: Name of the file with the authorized key.
  Result:
  id: aje8nn871qo4******** service_account_id: ajehr0to1g8b******** created_at: "2023-06-20T09:16:43.479156798Z" key_algorithm: RSA_2048
2. Create a CLI profile to run operations on behalf of the service account:
  yc config profile create sa-terraform
  Result:
  Profile 'sa-terraform' created and activated
3. Set the profile configuration:
  yc config set service-account-key key.json yc config set cloud-id <cloud_ID> yc config set folder-id <folder_ID>
  Where:
  - service-account-key: File with the service account authorized key.
  - cloud-id: Cloud ID.
  - folder-id: Folder ID.
4. Add the credentials to the environment variables:
  export YC_TOKEN=$(yc iam create-token)

Prepare the environment

Install the required utilities

Install Git using the following command:
```
sudo apt install git
```
Install Terraform.

Deploy your resources

Clone the GitHub repository and go to the yc-cr-private-endpoint script folder:

git clone https://github.com/yandex-cloud-examples/yc-cr-private-endpoint.git
cd yc-cr-private-endpoint

Open the terraform.tfvars file and edit the following:

String with the folder ID:
```
folder_id = "<folder_ID>"
```
String containing a list of aggregated prefixes of cloud subnets that are allowed to access Container Registry:
```
trusted_cloud_nets = ["10.0.0.0/8", "192.168.0.0/16"]
```

Description of variables in terraform.tfvars

Name name	Needs editing	Description	Type	Example
`folder_id`	Yes	ID of the folder to host the solution components	`string`	`b1gentmqf1ve9uc54nfh`
`vpc_id`	-	ID of the cloud network for which access to Container Registry is set up. If not specified, such network will be created.	`string`	`enp48c1ndilt42veuw4x`
`yc_availability_zones`	-	List of availability zones for deploying NAT instances	`list(string)`	`["ru-central1-a", "ru-central1-b"]`
`subnet_prefix_list`	-	List of prefixes of cloud subnets to host the NAT instances (one subnet in each availability zone from the `yc_availability_zones` list in the same order)	`list(string)`	`["10.10.1.0/24", "10.10.2.0/24"]`
`nat_instances_count`	-	Number of NAT instances to deploy. We recommend setting an even number to evenly distribute the instances across the availability zones.	`number`	`2`
`registry_private_access`	-	Only allow registry access from public IP addresses of NAT instances. `true` means the access is limited. To remove the limit, set `false`.	`bool`	`true`
`trusted_cloud_nets`	Yes	List of aggregated prefixes of cloud subnets that Container Registry access is allowed for. It is used in the rule for incoming traffic of security groups for the NAT instances.	`list(string)`	`["10.0.0.0/8", "192.168.0.0/16"]`
`vm_username`	-	NAT instance and test VM user names	`string`	`admin`
`cr_ip`	-	Container Registry public IP address	`string`	`84.201.171.239`
`cr_fqdn`	-	Container Registry domain name	`string`	`cr.yandex`
`s3_ip`	-	Object Storage public IP address	`string`	`213.180.193.243`
`s3_fqdn`	-	Object Storage domain name	`string`	`storage.yandexcloud.net`

Deploy the resources in the cloud using Terraform:
1. Initialize Terraform:
```
terraform init
```
2. Check the Terraform file configuration:
```
terraform validate
```
3. Check the list of cloud resources you are about to create:
```
terraform plan
```
4. Create resources:
```
terraform apply
```

Once the terraform apply process is completed, the command line will output information required for connecting to the test VM and running test operations with Container Registry. Later on, you can view this information by running the terraform output command:

Viewing information on deployed resources

Name	Description	Sample value
`cr_nlb_ip_address`	IP address of the internal load balancer for Container Registry	`10.10.1.100`
`cr_registry_id`	Registry ID in Container Registry	`crp1r4h00mj*********`
`path_for_private_ssh_key`	File with a private key used to connect to the NAT instances and test VM over SSH	`./pt_key.pem`
`s3_nlb_ip_address`	IP address of the internal load balancer for Object Storage	`10.10.1.200`
`test_vm_password`	`admin` user password for the test VM	`v3RCqUrQN?x)`
`vm_username`	NAT instance and test VM user names	`admin`

Test the solution

In the management console, go to the folder where the resources were created.
Select Compute Cloud.
Select test-cr-vm from the list of VM instances.
In the left-hand menu, select Serial console.
Click Connect.
Enter the admin username and the password from the terraform output test_vm_password command output (without quotation marks).
Run this command:
```
dig cr.yandex storage.yandexcloud.net
```
Make sure Object Storage and Container Registry domain names in the DNS server response match the IP addresses of the internal load balancers. The output of the type A resource records is as follows:
```
;; ANSWER SECTION:
cr.yandex.               300    IN      A       10.10.1.100

;; ANSWER SECTION:
storage.yandexcloud.net. 300    IN      A       10.10.1.200
```

View the list of available Docker images:

docker image list

Result:

REPOSITORY    TAG       IMAGE ID       CREATED        SIZE
golang        1.20.5    342*********   8 months ago   777MB
hello-world   latest    9c7*********   9 months ago   13.3kB

Assign a URL to the Docker image using the following format: cr.yandex/<registry_ID>/<Docker_image_name>:<tag>. The registry ID will be obtained from the test VM environment variable:

docker tag hello-world cr.yandex/$REGISTRY_ID/hello-world:demo

docker image list

Result:

REPOSITORY                                   TAG       IMAGE ID       CREATED        SIZE
golang                                       1.20.5    342*********   8 months ago   777MB
cr.yandex/crp1r4h00mj*********/hello-world   demo      9c7*********   9 months ago   13.3kB
hello-world                                  latest    9c7*********   9 months ago   13.3kB

Note

You can only push Docker images to Container Registry if they have a URL in this format: cr.yandex/<registry_ID>/<Docker_image_name>:<tag>.

Push the required Docker image to the registry:

docker push cr.yandex/$REGISTRY_ID/hello-world:demo

Result:

The push refers to repository [cr.yandex/crp1r4h00mj*********/hello-world]
01bb4*******: Pushed 
demo: digest: sha256:7e9b6e7ba284****************** size: 525

In the management console, go to the folder where the resources were created.
Select Container Registry.
Select the test-registry registry.
Make sure the hello-world repository with the Docker image appears in the registry.

Tips for deployment in the production environment

When deploying NAT instances in multiple availability zones, set an even number of VMs to evenly distribute them across the availability zones.
When selecting the number of NAT instances, consider the locality of traffic handling by the internal load balancer.
Once the solution is deployed, reduce the number of NAT instances or update the list of availability zones in the yc_availability_zones parameter only during a pre-scheduled time window. While applying changes, traffic handling may be interrupted.
If the CPU steal time metric of a NAT instance shows a high value as the Container Registry load goes up, we recommend enabling a software-accelerated network for that NAT instance.

If you are using your own DNS server, create type A resource records in its settings in the following format:

Name	Type	Value
`cr.yandex.`	`A`	`<IP address of the internal load balancer for Container Registry from the` terraform output cr_nlb_ip_address `command output>`
`storage.yandexcloud.net.`	`A`	`<IP address of the internal load balancer for Object Storage from the` terraform output s3_nlb_ip_address `command output>`

Save the pt_key.pem private SSH key used to connect to the NAT instances to a secure location or recreate it separately from Terraform.
Once the solution is deployed, SSH access to the NAT instances will be denied. To enable access to the NAT instances over SSH, add a rule for incoming SSH traffic (TCP/22) in the cr-nat-sg security group to enable access only from certain IP addresses of admin workstations.
After a performance check, delete the test VM and its subnet.

Delete the resources you created

In the management console, go to the folder where the resources were created.
Select Container Registry.
Select the test-registry registry.
Select the hello-world repository.
For each Docker image in the repository, click .
In the menu that opens, click Delete.
In the window that opens, click Delete.
To delete the resources you created using Terraform, run the terraform destroy command.

Warning

Terraform will permanently delete all the resources that were created while deploying the solution.

Connecting to Container Registry from Virtual Private Cloud

Prepare your cloudPrepare your cloud

Required paid resourcesRequired paid resources

Required quotasRequired quotas

Configure the CLI profileConfigure the CLI profile

Prepare the environmentPrepare the environment

Install the required utilitiesInstall the required utilities

Deploy your resourcesDeploy your resources

Test the solutionTest the solution

Tips for deployment in the production environmentTips for deployment in the production environment

Delete the resources you createdDelete the resources you created

Was the article helpful?

Prepare your cloud

Required paid resources

Required quotas

Configure the CLI profile

Prepare the environment

Install the required utilities

Deploy your resources

Test the solution

Tips for deployment in the production environment

Delete the resources you created