Create or update an EC2 launch template

EFA network interfaces are set up in the EC2 launch template for an AWS PCS compute node group. If there are multiple network cards, multiple EFAs can be configured. The EFA security group and the optional placement group are included in the launch template as well.

Here is an example launch template for instances with two network cards, such as hpc7a.96xlarge. The instances will be launched in subnet-SubnetID1 in cluster placement group pg-PlacementGroupId1.

Security groups must be added specifically to each EFA interface. Every EFA needs the security group that enables EFA traffic (sg-EfaSecGroupId). Other security groups, especially ones that handle regular traffic like SSH or HTTPS, only need to be attached to the primary network interface (designated by a DeviceIndex of 0). Launch templates where network interfaces are defined do not support setting security groups using the SecurityGroupIds parameter—you must set a value for Groups in each network interface that you configure.

{
    "Placement": {
        "GroupId": "pg-PlacementGroupId1"
    },
    "NetworkInterfaces": [
        {
            "DeviceIndex": 0,
            "InterfaceType": "efa",
            "NetworkCardIndex": 0,
            "SubnetId": "subnet-SubnetId1",
            "Groups": [
                "sg-SecurityGroupId1",
                "sg-EfaSecGroupId"
            ]
        },
        {
            "DeviceIndex": 1,
            "InterfaceType": "efa",
            "NetworkCardIndex": 1,
            "SubnetId": "subnet-SubnetId1"
            "Groups": ["sg-EfaSecGroupId"]
        }
    ]
}