Fix comment (#290)

create-slurm-security-groups/create_slurm_security_groups/create_slurm_security_groups_stack.py

@@ -106,7 +106,8 @@ def __init__(self, scope: Construct, construct_id: str, **kwargs) -> None:
             security_groups['SlurmdbdSG'] = slurmdbd_sg
 
         # Rules for compute nodes
-        # Allow mounting of /opt/slurm and from head node
+        # Allow mounting of /opt/slurm from the head node.
+        # This is needed in XIO VMs. ParallelCluster compute nodes have a local copy on their root volume.
         slurm_compute_node_sg.connections.allow_to(slurm_head_node_sg, ec2.Port.tcp(2049), f"SlurmComputeNodeSG to SlurmHeadNodeSG NFS")
 
         # Rules for login nodes