diff --git a/cmd/endpoint-ellipses.go b/cmd/endpoint-ellipses.go
index 57713b94d..6ced9915c 100644
--- a/cmd/endpoint-ellipses.go
+++ b/cmd/endpoint-ellipses.go
@@ -1,5 +1,5 @@
 /*
- * MinIO Cloud Storage, (C) 2018 MinIO, Inc.
+ * MinIO Cloud Storage, (C) 2018-2020 MinIO, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -108,12 +108,24 @@ func getSetIndexes(args []string, totalSizes []uint64, customSetDriveCount uint6
 		return ss
 	}
 
+	setCounts := possibleSetCounts(commonSize)
+	if len(setCounts) == 0 {
+		msg := fmt.Sprintf("Incorrect number of endpoints provided %s, number of disks %d is not divisible by any supported erasure set sizes %d", args, commonSize, setSizes)
+		return nil, config.ErrInvalidNumberOfErasureEndpoints(nil).Msg(msg)
+	}
+
 	if customSetDriveCount > 0 {
-		msg := fmt.Sprintf("Invalid set drive count, leads to non-uniform distribution for the given number of disks. Possible values for custom set count are %d", possibleSetCounts(setSize))
+		msg := fmt.Sprintf("Invalid set drive count. Acceptable values for %d number drives are %d", commonSize, setCounts)
 		if customSetDriveCount > setSize {
 			return nil, config.ErrInvalidErasureSetSize(nil).Msg(msg)
 		}
-		if setSize%customSetDriveCount != 0 {
+		var found bool
+		for _, ss := range setCounts {
+			if ss == customSetDriveCount {
+				found = true
+			}
+		}
+		if !found {
 			return nil, config.ErrInvalidErasureSetSize(nil).Msg(msg)
 		}
 		setSize = customSetDriveCount
@@ -121,7 +133,7 @@ func getSetIndexes(args []string, totalSizes []uint64, customSetDriveCount uint6
 
 	// Check whether setSize is with the supported range.
 	if !isValidSetSize(setSize) {
-		msg := fmt.Sprintf("Incorrect number of endpoints provided %s", args)
+		msg := fmt.Sprintf("Incorrect number of endpoints provided %s, number of disks %d is not divisible by any supported erasure set sizes %d", args, commonSize, setSizes)
 		return nil, config.ErrInvalidNumberOfErasureEndpoints(nil).Msg(msg)
 	}
 
@@ -261,9 +273,6 @@ func createServerEndpoints(serverAddr string, args ...string) (
 		if err != nil {
 			return nil, -1, -1, config.ErrInvalidErasureSetSize(err)
 		}
-		if !isValidSetSize(uint64(setDriveCount)) {
-			return nil, -1, -1, config.ErrInvalidErasureSetSize(nil)
-		}
 	}
 
 	if !ellipses.HasEllipses(args...) {
diff --git a/cmd/endpoint-ellipses_test.go b/cmd/endpoint-ellipses_test.go
index 27a8ddc29..cb6bbc4f2 100644
--- a/cmd/endpoint-ellipses_test.go
+++ b/cmd/endpoint-ellipses_test.go
@@ -104,6 +104,36 @@ func TestGetSetIndexesEnvOverride(t *testing.T) {
 			8,
 			true,
 		},
+		{
+			[]string{"http://host{1...12}/data{1...12}"},
+			[]uint64{144},
+			[][]uint64{{16, 16, 16, 16, 16, 16, 16, 16, 16}},
+			16,
+			true,
+		},
+		{
+			[]string{"http://host{0...5}/data{1...28}"},
+			[]uint64{168},
+			[][]uint64{{12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12}},
+			12,
+			true,
+		},
+		// Incorrect custom set drive count.
+		{
+			[]string{"http://host{0...5}/data{1...28}"},
+			[]uint64{168},
+			nil,
+			10,
+			false,
+		},
+		// Failure not divisible number of disks.
+		{
+			[]string{"http://host{1...11}/data{1...11}"},
+			[]uint64{121},
+			nil,
+			11,
+			false,
+		},
 		{
 			[]string{"data{1...60}"},
 			nil,
diff --git a/cmd/format-xl.go b/cmd/format-xl.go
index 7fdb93324..6adbf1213 100644
--- a/cmd/format-xl.go
+++ b/cmd/format-xl.go
@@ -426,7 +426,7 @@ func checkFormatXLValue(formatXL *formatXLV3) error {
 }
 
 // Check all format values.
-func checkFormatXLValues(formats []*formatXLV3) error {
+func checkFormatXLValues(formats []*formatXLV3, drivesPerSet int) error {
 	for i, formatXL := range formats {
 		if formatXL == nil {
 			continue
@@ -438,6 +438,9 @@ func checkFormatXLValues(formats []*formatXLV3) error {
 			return fmt.Errorf("%s disk is already being used in another erasure deployment. (Number of disks specified: %d but the number of disks found in the %s disk's format.json: %d)",
 				humanize.Ordinal(i+1), len(formats), humanize.Ordinal(i+1), len(formatXL.XL.Sets)*len(formatXL.XL.Sets[0]))
 		}
+		if len(formatXL.XL.Sets[0]) != drivesPerSet {
+			return fmt.Errorf("%s disk is already formatted with %d drives per erasure set. This cannot be changed to %d, please revert your MINIO_ERASURE_SET_DRIVE_COUNT setting", humanize.Ordinal(i+1), len(formatXL.XL.Sets[0]), drivesPerSet)
+		}
 	}
 	return nil
 }
diff --git a/cmd/prepare-storage.go b/cmd/prepare-storage.go
index fb80442ec..ce3b7bda0 100644
--- a/cmd/prepare-storage.go
+++ b/cmd/prepare-storage.go
@@ -255,7 +255,7 @@ func connectLoadInitFormats(retryCount int, firstDisk bool, endpoints Endpoints,
 	// most part unless one of the formats is not consistent
 	// with expected XL format. For example if a user is
 	// trying to pool FS backend into an XL set.
-	if err := checkFormatXLValues(formatConfigs); err != nil {
+	if err := checkFormatXLValues(formatConfigs, drivesPerSet); err != nil {
 		return nil, err
 	}
 
diff --git a/cmd/xl-sets.go b/cmd/xl-sets.go
index a7e2da157..3f7ef52d1 100644
--- a/cmd/xl-sets.go
+++ b/cmd/xl-sets.go
@@ -1293,7 +1293,7 @@ func (s *xlSets) ReloadFormat(ctx context.Context, dryRun bool) (err error) {
 	}(storageDisks)
 
 	formats, sErrs := loadFormatXLAll(storageDisks)
-	if err = checkFormatXLValues(formats); err != nil {
+	if err = checkFormatXLValues(formats, s.drivesPerSet); err != nil {
 		return err
 	}
 
@@ -1406,7 +1406,7 @@ func (s *xlSets) HealFormat(ctx context.Context, dryRun bool) (res madmin.HealRe
 	markRootDisksAsDown(storageDisks)
 
 	formats, sErrs := loadFormatXLAll(storageDisks)
-	if err = checkFormatXLValues(formats); err != nil {
+	if err = checkFormatXLValues(formats, s.drivesPerSet); err != nil {
 		return madmin.HealResultItem{}, err
 	}