This topic describes the possible causes of and solutions to the following issue: You created a vSwitch, but when you create a Tair (Redis OSS-compatible) instance, change the network type of an instance, or migrate an instance to another zone, the vSwitch drop-down list is empty or does not contain the vSwitch.
Possible causes
The vSwitch was not created within the current account.
The vSwitch you created does not reside in the zone or the VPC that you selected.
Solutions
Change the VPC or zone, and then find and select the created vSwitch.
Create a vSwitch in the zone that you selected. For more information, see Create and manage a vSwitch.