Fix desired size of eks node group

[maxsxu]

Motivation

Encountering error "invalid desiredSize" while applying with below input variables:

node_pool_min_size = 1
node_pool_max_size = 12
node_pool_desired_size = 1
node_pool_instance_types = ["c6i.2xlarge"]

That's caused by the computed desired size via node_pool_instance_types could be 0., which violates the rule "Desired number of nodes should not be lower than the minimum number of nodes that the group can scale out to."

Actually the desired_size has already been assigned in its above code block node_group_defaults:

terraform-aws-cloud/main.tf

Line 82 in e0e7315

desired_size = var.node_pool_desired_size

We should just respect it.

Modifications

• Remove the duplicated desired_size assignment line

Verifying this change

• Make sure that the change passes the CI checks.

This change is a trivial rework / code cleanup without any test coverage.

Documentation

• no-need-doc

[ignacioli]

LGTM

[gengmao]

Can node_pool_min_size be 0? New terraform code create one pool per instance type and subnet. Will it cause waste?

[maxsxu]

Can node_pool_min_size be 0?

Yes. The scaling config rules for a node group according to https://docs.aws.amazon.com/eks/latest/APIReference/API_NodegroupScalingConfig.html:

• minSize $\ge$ 0
• maxSize $\ge$ 1
• desiredSize $\ge$ 0
• minSize $\le$ desiredSize $\le$ maxSize

New terraform code create one pool per instance type and subnet. Will it cause waste?

IMO, It should be ok, as we can specify the node_pool_max_size so the node group autoscaling will take care of the number of real EC2 instances.