If you reconfigure the IPv4 CIDR blocks for Realtime Compute for Apache Flink or encounter the issue that a deployment fails to start, you may need to modify a vSwitch to resolve the issue. This topic describes how to modify a vSwitch.
Precautions
When you add a vSwitch to Realtime Compute for Apache Flink, you must configure the CIDR blocks for Realtime Compute for Apache Flink based on your business requirements. When you add a vSwitch to Realtime Compute for Apache Flink, make sure that the number of available IP addresses of the vSwitch is sufficient. If the number of IP addresses of the vSwitch is insufficient, deployments may fail to start or the development console of Realtime Compute for Apache Flink cannot be upgraded.
If you want to configure a whitelist for the upstream and downstream storage of a Realtime Compute for Apache Flink deployment, you must add the CIDR blocks of the vSwitch of the deployment to the whitelist of the upstream and downstream storage.
If you want to use a new vSwitch during the network architecture upgrade, we recommend that you do not immediately delete the old vSwitch. You can delete the old vSwitch until the next time the deployments are restarted. This is because deployments that are started continue to use the old vSwitch when you delete the old vSwitch and use the new vSwitch.
Procedure
Log on to the management console of Realtime Compute for Apache Flink.
Find the workspace that you want to manage and choose in the Actions column.
In the Modify vSwitches dialog box, select the vSwitch that you want to add.
The vSwitch that you add must reside in the same virtual private cloud (VPC) as the Realtime Compute for Apache Flink workspace and in a zone that is supported by Realtime Compute for Apache Flink.
If no vSwitch meets your business requirements in the vSwitch list, click Create vSwitch in the note at the top of the list to create a vSwitch. After you create the vSwitch, click the
icon in the upper-left corner of the list to refresh the Modify vSwitches dialog box and select the new vSwitch.
Click OK.
ImportantIf you want to use a new vSwitch during the network architecture upgrade, we recommend that you do not immediately delete the old vSwitch. You can delete the old vSwitch until the next time the deployments are restarted. This is because deployments that are started continue to use the old vSwitch when you delete the old vSwitch and use the new vSwitch.
References
After the network architecture of Realtime Compute for Apache Flink is upgraded, the number of IP addresses that are used by your vSwitch can be significantly reduced. For more information, see Network architecture upgrade.
By default, Realtime Compute for Apache Flink cannot access the Internet. Therefore, Alibaba Cloud provides NAT gateways to enable communications between VPCs and the Internet. You can create a NAT gateway in a VPC. Then, create a source network address translation (SNAT) entry to bind the vSwitch that is associated with Realtime Compute for Apache Flink to an elastic IP address (EIP). This way, the service can access the Internet by using the EIP. For more information, see FAQ about network connectivity.