Hello, dear!
A security group implements access control for VMs within a security group or in different security groups, enhancing VM security. After a security group is created by a VDC administrator, you can define access rules in it. These rules take effect for all added VMs. If the AZ type is VMware, ServiceCenter does not support the security group function. This section instructs VDC administrators to add a VM to a security group.
Step 1 Choose Console > VMs from the main menu. On the displayed VMs page, locate the row that contains the VM to be added to a security group, and click
to expand the VM details.

Step 2 Click
next to NIC.

Step 3 Locate the row that contains the NIC of the VM to be added to the security group, and choose More > Join Security Group.

Step 4 Select a security group and click OK.

Thanks!