How to modify the parameters of ENI attached to the ECS Instance?

Question

When I am trying to change the security group for the ENI attached to the ECS Instance, It shows you can`t change the parameter of Primary ENI. I understand the parameter of the primary ENI cannot be changed. Is there any workaround available? Can I able to add new ENI as primary?

Answer 1

You can modify attributes of a secondary ENI, but not the primary ENI, of an instance. You can modify the following attributes of an ENI:

• The name of the ENI.
• The security group associated with the ENI. One ENI must be associated with at least one security group. However, it cannot be associated with more than five security groups.
• Description of the ENI.

You can modify attributes of an ENI when it is in the Available or the InUse status. This document describes how to modify attributes of an ENI in the ECS console.

To modify attributes of an ENI, follow these steps:

1. Log on to the ECS console.
2. In the left-side navigation pane, selectNetworks & Security > Network Interfaces.
3. Select a region.
4. Find an ENI, and in the Actions column, click Modify.
5. In the Modify dialog box, modify the following optional configurations:
   • Network Interface Name: Specify a new name for the selected ENI.
   • SecurityGroup: Select more security groups for the ENI, or remove security groups. Retain at least one security group.
   • Description: Give a brief description for the ENI. After you finish the modification, click OK.

Alibaba Cloud Official Documentation Available Here

Answer 2

AFAIK there is no workaround here. There are several functionalities that ECS provides like

1. Attach an ENI Instance
2. Detach an ENI instance
3. Modify attributes of an ENI

Sadly, I see you can only detach a secondary ENI, but not a primary ENI and also as you said attributes modification also allows only for the secondary Instance. I am exploring if this something I can do it via API, but still in progress. I will keep this answer updated when I find a way