anchor.diff:  An instance group is a kops concept that defines a grouping of similar machines. In AWS, an instance group maps to an
   AutoScalingGroup (ASG).
   
  -In this section we'll look at different ways of using kops instance groups in a Kubernetes cluster:
  -
  -. Update the instance group by adjusting its size, or the instance types it contains
  -. Add an additional instance group to a cluster, and schedule pods on the instances in the new instance group
  -. Pin an instance group pinned to a specific AZ
  +In this section we'll look at different ways of using kops instance groups in a Kubernetes cluster, including:
  +
  +. Updating the instance group by adjusting its size, or the instance types it contains
  +. Adding an additional instance group to a cluster, and scheduling pods on the instances in the new instance group
  +. Pinning an instance group to a specific AZ
   
   == Basic instance group commands
   
  -List the instance groups in your cluster:
  +Your Kubernetes cluster already has a couple of instance groups that were created by kops: one instance group for
  +the worker nodes, another for the master nodes. List the instance groups in your cluster:
   
       kops get ig
   
     $ kops get ig
       Using cluster from kubectl context: cluster.k8s.local
  -
       NAME			    ROLE	MACHINETYPE	MIN	MAX	SUBNETS
       master-us-east-1d	Master	m3.medium	1	1	us-east-1d
       nodes			    Node	t2.medium	2	6	us-east-1d,us-east-1e
  
positive.code: Changes may require instances to restart: kops rolling-update cluster
  
  ```
  The output of the 'update cluster' hints that a rolling update may be required. Since we are only updating the size
  of the instance group, no rolling update is necessary. In the next example we'll make an update where a rolling update will
  be required.
  
  
negative.code: .
  Will modify resources:
    LaunchConfiguration/nodes.cluster.k8s.local
    	InstanceType        	 t2.medium -> m4.large
  
  Must specify --yes to apply changes
  ```
  