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Co-authored-by: Michael Schurter <mschurter@hashicorp.com>

.changelog/12008.txt

@@ -1,3 +1,3 @@
 ```release-note:improvement
-scheduler: Seed the shuffling of nodes with the evaluation ID to improve debuggability
+scheduler: Seed node shuffling with the evaluation ID to make the order reproducible
 ```

scheduler/util.go

@@ -379,7 +379,7 @@ func taintedNodes(state State, allocs []*structs.Allocation) (map[string]*struct
 
 // shuffleNodes randomizes the slice order with the Fisher-Yates
 // algorithm. We seed the random source with the eval ID (which is
-// random) to aid in postmortem debuggging of specific evaluations and
+// random) to aid in postmortem debugging of specific evaluations and
 // state snapshots.
 func shuffleNodes(plan *structs.Plan, nodes []*structs.Node) {
 
@@ -388,12 +388,9 @@ func shuffleNodes(plan *structs.Plan, nodes []*structs.Node) {
 	buf := []byte(plan.EvalID)
 	seed := int64(binary.BigEndian.Uint32(buf[len(buf)-4:]))
 
-	// include the plan progress so that we don't retry with
+	// include the plan result's RefreshIndex so that we don't retry with
 	// the exact same shuffle
-	seed = seed |
-		int64(len(plan.NodeAllocation)) |
-		int64(len(plan.NodeUpdate)) |
-		int64(len(plan.DeploymentUpdates))
+	seed |= planResult.RefreshIndex
 
 	r := rand.New(rand.NewSource(seed))