fix: add stricter validation for erasure server pools (#11299)

During expansion we need to validate if

- new deployment is expanded with newer constraints
- existing deployment is expanded with older constraints
- multiple server pools rejected if they have different
  deploymentID and distribution algo

Makefile

@@ -38,7 +38,7 @@ fmt:
 lint:
 	@echo "Running $@ check"
 	@GO111MODULE=on ${GOPATH}/bin/golangci-lint cache clean
-	@GO111MODULE=on ${GOPATH}/bin/golangci-lint run --timeout=5m --config ./.golangci.yml
+	@GO111MODULE=on ${GOPATH}/bin/golangci-lint run --timeout=10m --config ./.golangci.yml
 
 ruleguard:
 	@echo "Running $@ check"

cmd/endpoint-ellipses.go

@@ -363,19 +363,12 @@ func createServerEndpoints(serverAddr string, args ...string) (
 	}
 
 	var foundPrevLocal bool
-	var commonParityDrives int
-
 	for _, arg := range args {
 		setArgs, err := GetAllSets(arg)
 		if err != nil {
 			return nil, -1, err
 		}
 
-		parityDrives := ecDrivesNoConfig(len(setArgs[0]))
-		if commonParityDrives != 0 && commonParityDrives != parityDrives {
-			return nil, -1, fmt.Errorf("All serverPools should have same parity ratio - expected %d, got %d", commonParityDrives, parityDrives)
-		}
-
 		endpointList, gotSetupType, err := CreateEndpoints(serverAddr, foundPrevLocal, setArgs...)
 		if err != nil {
 			return nil, -1, err
@@ -388,10 +381,6 @@ func createServerEndpoints(serverAddr string, args ...string) (
 			return nil, -1, err
 		}
 		foundPrevLocal = endpointList.atleastOneEndpointLocal()
-		if commonParityDrives == 0 {
-			commonParityDrives = ecDrivesNoConfig(len(setArgs[0]))
-		}
-
 		if setupType == UnknownSetupType {
 			setupType = gotSetupType
 		}

cmd/erasure-server-pool.go

@@ -55,8 +55,11 @@ func (z *erasureServerPools) SingleZone() bool {
 // Initialize new pool of erasure sets.
 func newErasureServerPools(ctx context.Context, endpointServerPools EndpointServerPools) (ObjectLayer, error) {
 	var (
-		deploymentID string
+		deploymentID       string
-		err          error
+		distributionAlgo   string
+		commonParityDrives int
+		drivesPerSet       int
+		err                error
 
 		formats      = make([]*formatErasureV3, len(endpointServerPools))
 		storageDisks = make([][]StorageAPI, len(endpointServerPools))
@@ -72,15 +75,54 @@ func newErasureServerPools(ctx context.Context, endpointServerPools EndpointServ
 				localDrives = append(localDrives, endpoint.Path)
 			}
 		}
+
+		if drivesPerSet == 0 {
+			drivesPerSet = ep.DrivesPerSet
+		}
+
+		if commonParityDrives == 0 {
+			commonParityDrives = ecDrivesNoConfig(ep.DrivesPerSet)
+		}
+
+		// Once distribution algo is set, validate it for the next pool,
+		// before proceeding to write to drives.
+		switch distributionAlgo {
+		case formatErasureVersionV3DistributionAlgoV2:
+			if drivesPerSet != 0 && drivesPerSet != ep.DrivesPerSet {
+				return nil, fmt.Errorf("All legacy serverPools should have same drive per set ratio - expected %d, got %d", drivesPerSet, ep.DrivesPerSet)
+			}
+		case formatErasureVersionV3DistributionAlgoV3:
+			parityDrives := ecDrivesNoConfig(ep.DrivesPerSet)
+			if commonParityDrives != 0 && commonParityDrives != parityDrives {
+				return nil, fmt.Errorf("All current serverPools should have same parity ratio - expected %d, got %d", commonParityDrives, parityDrives)
+			}
+		}
+
 		storageDisks[i], formats[i], err = waitForFormatErasure(local, ep.Endpoints, i+1,
-			ep.SetCount, ep.DrivesPerSet, deploymentID)
+			ep.SetCount, ep.DrivesPerSet, deploymentID, distributionAlgo)
 		if err != nil {
 			return nil, err
 		}
+
 		if deploymentID == "" {
 			// all zones should have same deployment ID
 			deploymentID = formats[i].ID
 		}
+
+		if distributionAlgo == "" {
+			distributionAlgo = formats[i].Erasure.DistributionAlgo
+		}
+
+		// Validate if users brought different DeploymentID pools.
+		if deploymentID != formats[i].ID {
+			return nil, fmt.Errorf("All serverPools should have same deployment ID expected %s, got %s", deploymentID, formats[i].ID)
+		}
+
+		// Validate if users brought different different distribution algo pools.
+		if distributionAlgo != formats[i].Erasure.DistributionAlgo {
+			return nil, fmt.Errorf("All serverPools should have same distributionAlgo expected %s, got %s", distributionAlgo, formats[i].Erasure.DistributionAlgo)
+		}
+
 		z.serverPools[i], err = newErasureSets(ctx, ep.Endpoints, storageDisks[i], formats[i])
 		if err != nil {
 			return nil, err

cmd/erasure-sets_test.go

@@ -173,18 +173,18 @@ func TestNewErasureSets(t *testing.T) {
 	}
 
 	endpoints := mustGetNewEndpoints(erasureDisks...)
-	_, _, err := waitForFormatErasure(true, endpoints, 1, 0, 16, "")
+	_, _, err := waitForFormatErasure(true, endpoints, 1, 0, 16, "", "")
 	if err != errInvalidArgument {
 		t.Fatalf("Expecting error, got %s", err)
 	}
 
-	_, _, err = waitForFormatErasure(true, nil, 1, 1, 16, "")
+	_, _, err = waitForFormatErasure(true, nil, 1, 1, 16, "", "")
 	if err != errInvalidArgument {
 		t.Fatalf("Expecting error, got %s", err)
 	}
 
 	// Initializes all erasure disks
-	storageDisks, format, err := waitForFormatErasure(true, endpoints, 1, 1, 16, "")
+	storageDisks, format, err := waitForFormatErasure(true, endpoints, 1, 1, 16, "", "")
 	if err != nil {
 		t.Fatalf("Unable to format disks for erasure, %s", err)
 	}

cmd/format-erasure.go

@@ -837,7 +837,7 @@ func fixFormatErasureV3(storageDisks []StorageAPI, endpoints Endpoints, formats
 }
 
 // initFormatErasure - save Erasure format configuration on all disks.
-func initFormatErasure(ctx context.Context, storageDisks []StorageAPI, setCount, setDriveCount int, deploymentID string, sErrs []error) (*formatErasureV3, error) {
+func initFormatErasure(ctx context.Context, storageDisks []StorageAPI, setCount, setDriveCount int, deploymentID, distributionAlgo string, sErrs []error) (*formatErasureV3, error) {
 	format := newFormatErasureV3(setCount, setDriveCount)
 	formats := make([]*formatErasureV3, len(storageDisks))
 	wantAtMost := ecDrivesNoConfig(setDriveCount)
@@ -848,6 +848,9 @@ func initFormatErasure(ctx context.Context, storageDisks []StorageAPI, setCount,
 			disk := storageDisks[i*setDriveCount+j]
 			newFormat := format.Clone()
 			newFormat.Erasure.This = format.Erasure.Sets[i][j]
+			if distributionAlgo != "" {
+				newFormat.Erasure.DistributionAlgo = distributionAlgo
+			}
 			if deploymentID != "" {
 				newFormat.ID = deploymentID
 			}

cmd/prepare-storage.go

@@ -228,7 +228,7 @@ func isServerResolvable(endpoint Endpoint) error {
 // connect to list of endpoints and load all Erasure disk formats, validate the formats are correct
 // and are in quorum, if no formats are found attempt to initialize all of them for the first
 // time. additionally make sure to close all the disks used in this attempt.
-func connectLoadInitFormats(retryCount int, firstDisk bool, endpoints Endpoints, poolCount, setCount, setDriveCount int, deploymentID string) (storageDisks []StorageAPI, format *formatErasureV3, err error) {
+func connectLoadInitFormats(retryCount int, firstDisk bool, endpoints Endpoints, poolCount, setCount, setDriveCount int, deploymentID, distributionAlgo string) (storageDisks []StorageAPI, format *formatErasureV3, err error) {
 	// Initialize all storage disks
 	storageDisks, errs := initStorageDisksWithErrors(endpoints)
 
@@ -276,7 +276,7 @@ func connectLoadInitFormats(retryCount int, firstDisk bool, endpoints Endpoints,
 			humanize.Ordinal(poolCount), setCount, setDriveCount)
 
 		// Initialize erasure code format on disks
-		format, err = initFormatErasure(GlobalContext, storageDisks, setCount, setDriveCount, deploymentID, sErrs)
+		format, err = initFormatErasure(GlobalContext, storageDisks, setCount, setDriveCount, deploymentID, distributionAlgo, sErrs)
 		if err != nil {
 			return nil, nil, err
 		}
@@ -345,7 +345,7 @@ func connectLoadInitFormats(retryCount int, firstDisk bool, endpoints Endpoints,
 }
 
 // Format disks before initialization of object layer.
-func waitForFormatErasure(firstDisk bool, endpoints Endpoints, poolCount, setCount, setDriveCount int, deploymentID string) ([]StorageAPI, *formatErasureV3, error) {
+func waitForFormatErasure(firstDisk bool, endpoints Endpoints, poolCount, setCount, setDriveCount int, deploymentID, distributionAlgo string) ([]StorageAPI, *formatErasureV3, error) {
 	if len(endpoints) == 0 || setCount == 0 || setDriveCount == 0 {
 		return nil, nil, errInvalidArgument
 	}
@@ -372,7 +372,7 @@ func waitForFormatErasure(firstDisk bool, endpoints Endpoints, poolCount, setCou
 	for {
 		select {
 		case <-ticker.C:
-			storageDisks, format, err := connectLoadInitFormats(tries, firstDisk, endpoints, poolCount, setCount, setDriveCount, deploymentID)
+			storageDisks, format, err := connectLoadInitFormats(tries, firstDisk, endpoints, poolCount, setCount, setDriveCount, deploymentID, distributionAlgo)
 			if err != nil {
 				tries++
 				switch err {