Describe new node state update option of "DRAIN".

doc/html/quickstart.html

@@ -307,6 +307,9 @@ scontrol: update JobId=477 Priority=0
 </pre>
 <p>
 Print the state of node <i>adev13</i> and drain it.
+To drain a node specify a new state of "DRAIN", "DRAINED", or "DRAINING".
+SLURM will automatically set it to the appropriate value of either "DRAINING"
+or "DRAINED" depending if the node is allocated or not.
 Return it to service later.
 <pre>
 adev0: scontrol

doc/man/man1/scontrol.1

@@ -159,9 +159,12 @@ simple regular expressions (e.g. "lx[10-20]"). This specification is required.
 .TP
 \fIState\fP=<state>
 Identify the state to be assigned to the node. Possible values are  "NoResp", 
-"DOWN", "IDLE", "DRAINED", "DRAINING", and "ALLOCATED". The "NoResp" state 
-will only set the "NoResp" flag for a node without changing its underlying 
-state.
+"DOWN", "IDLE", "DRAIN", "DRAINED", "DRAINING", and "ALLOCATED". 
+To drain a node specify "DRAIN", "DRAINED", or "DRAINING".
+SLURM will automatically set it to the appropriate value of either 
+"DRAINING" or "DRAINED" depending if the node is allocated or not.
+The "NoResp" state will only set the "NoResp" flag for a node without
+changing its underlying state.
 .TP
 \fBSPECIFICATIONS FOR UPDATE COMMAND, PARTITIONS\fR
 .TP