Operation scenario: when purchasing an instance, if you select VPC and choose a corresponding VPC environment (such as VPC A), then CKafka services (such as data production and consumption) can be accessed only from VPC A. If you subsequently find that you need to access the CKafka services in VPC A from other VPCs (such as VPC B), you can select an appropriate routing policy for VPC by configuring the access mode.

Suggestion: to ensure security, this access mode provides user management and ACL policy configuration to manage user access permission. Configure as appropriate.

Directions:

1. Log in to the CKafka console.
2. Click Instance List on the left sidebar and click the ID/Name of the target instance to enter the basic information page.
3. On the instance basic information page, click Add a routing policy in the Access Mode module.
4. In the pop-up window, select VPC Network as the route type and select the access mode and network.
   
5. Click Submit to add the VPC network.
   The VPC access address provided in the console (such as 172.16.0.12:9092) represents the communication address used to obtain the backend service. There may be multiple ports in a real access address. You need to open all ports after 9092 to the internet on your server, so that the service can be accessed normally.

Operation scenario: if your consumer or producer is located in a self-built data center or another cloud, you can produce and consume data in CKafka through public network access.

Suggestion: to ensure security, Kafka offers various security authentication mechanisms, which mainly fall into the SSL and SASL2 categories. Among them, SASL/PLAIN is an authentication method based on account and password and more commonly used. CKafka supports SASL_PLAINTEXT and SASL_SSL authentication. You are recommended to configure the authentication method as appropriate when selecting public domain name access.

Directions:

1. Log in to the CKafka console.
2. Click Instance List on the left sidebar and click the ID/Name of the target instance to enter the basic information page.
3. On the instance basic information page, click Add a routing policy in the Access Mode module.
4. In the pop-up window, select Public domain name access as the route type and select the access mode and network.
   
5. Click Submit to add the public network routing policy.
   >?CKafka provides 3 Mbps public network bandwidth free of charge by default, which can be increased to up to 198 Mbps for Pro Edition instances. For detailed directions, see Upgrading public network bandwidth.