use features to simplify nodeset configuration

Author: sjpb

templates/slurm.conf.j2

@@ -158,6 +158,7 @@ Epilog=/etc/slurm/slurm.epilog.clean
 {%          set hostlists = (inventory_group_hosts | hostlist_expression) %}{# hosts in inventory group aren't necessarily a single hostlist expression #}
 {%              for hostlist in  hostlists %}
 NodeName={{ hostlist }} {{ '' -}}
+    Feature=nodegroup_{{ nodegroup.name }} {{ '' -}}
     State=UNKNOWN {{ '' -}}
     RealMemory={{ nodegroup.ram_mb | default(ram_mb) }} {{ '' -}}
     Sockets={{first_host_hv['ansible_processor_count'] }} {{ '' -}}
@@ -168,7 +169,7 @@ NodeName={{ hostlist }} {{ '' -}}
 {%              endfor %}{# hostlists #}
 {%      endif %}{# 1 or more hosts in inventory #}
 
-NodeSet={{ nodegroup.name }} Nodes={{ ','.join(hostlists | default(['""'])) }}{# no support for creating nodesets by Feature #}
+NodeSet=nodegroup_{{ nodegroup.name }} Feature=nodegroup_{{ nodegroup.name }}{# no support for creating nodesets by Feature #}
 
 {% endfor %}