package shell import ( "context" "fmt" "io" "math/rand" "sort" "github.com/chrislusf/seaweedfs/weed/operation" "github.com/chrislusf/seaweedfs/weed/pb/master_pb" "github.com/chrislusf/seaweedfs/weed/pb/volume_server_pb" "github.com/chrislusf/seaweedfs/weed/storage/super_block" ) func init() { Commands = append(Commands, &commandVolumeFixReplication{}) } type commandVolumeFixReplication struct { } func (c *commandVolumeFixReplication) Name() string { return "volume.fix.replication" } func (c *commandVolumeFixReplication) Help() string { return `add replicas to volumes that are missing replicas This command file all under-replicated volumes, and find volume servers with free slots. If the free slots satisfy the replication requirement, the volume content is copied over and mounted. volume.fix.replication -n # do not take action volume.fix.replication # actually copying the volume files and mount the volume Note: * each time this will only add back one replica for one volume id. If there are multiple replicas are missing, e.g. multiple volume servers are new, you may need to run this multiple times. * do not run this too quick within seconds, since the new volume replica may take a few seconds to register itself to the master. ` } func (c *commandVolumeFixReplication) Do(args []string, commandEnv *CommandEnv, writer io.Writer) (err error) { takeAction := true if len(args) > 0 && args[0] == "-n" { takeAction = false } var resp *master_pb.VolumeListResponse ctx := context.Background() err = commandEnv.MasterClient.WithClient(ctx, func(client master_pb.SeaweedClient) error { resp, err = client.VolumeList(ctx, &master_pb.VolumeListRequest{}) return err }) if err != nil { return err } // find all volumes that needs replication // collect all data nodes replicatedVolumeLocations := make(map[uint32][]location) replicatedVolumeInfo := make(map[uint32]*master_pb.VolumeInformationMessage) var allLocations []location eachDataNode(resp.TopologyInfo, func(dc string, rack RackId, dn *master_pb.DataNodeInfo) { loc := newLocation(dc, string(rack), dn) for _, v := range dn.VolumeInfos { if v.ReplicaPlacement > 0 { replicatedVolumeLocations[v.Id] = append(replicatedVolumeLocations[v.Id], loc) replicatedVolumeInfo[v.Id] = v } } allLocations = append(allLocations, loc) }) // find all under replicated volumes underReplicatedVolumeLocations := make(map[uint32][]location) for vid, locations := range replicatedVolumeLocations { volumeInfo := replicatedVolumeInfo[vid] replicaPlacement, _ := super_block.NewReplicaPlacementFromByte(byte(volumeInfo.ReplicaPlacement)) if replicaPlacement.GetCopyCount() > len(locations) { underReplicatedVolumeLocations[vid] = locations } } if len(underReplicatedVolumeLocations) == 0 { return fmt.Errorf("no under replicated volumes") } if len(allLocations) == 0 { return fmt.Errorf("no data nodes at all") } // find the most under populated data nodes keepDataNodesSorted(allLocations) for vid, locations := range underReplicatedVolumeLocations { volumeInfo := replicatedVolumeInfo[vid] replicaPlacement, _ := super_block.NewReplicaPlacementFromByte(byte(volumeInfo.ReplicaPlacement)) foundNewLocation := false for _, dst := range allLocations { // check whether data nodes satisfy the constraints if dst.dataNode.FreeVolumeCount > 0 && satisfyReplicaPlacement(replicaPlacement, locations, dst) { // ask the volume server to replicate the volume sourceNodes := underReplicatedVolumeLocations[vid] sourceNode := sourceNodes[rand.Intn(len(sourceNodes))] foundNewLocation = true fmt.Fprintf(writer, "replicating volume %d %s from %s to dataNode %s ...\n", volumeInfo.Id, replicaPlacement, sourceNode.dataNode.Id, dst.dataNode.Id) if !takeAction { break } err := operation.WithVolumeServerClient(dst.dataNode.Id, commandEnv.option.GrpcDialOption, func(ctx context.Context, volumeServerClient volume_server_pb.VolumeServerClient) error { _, replicateErr := volumeServerClient.VolumeCopy(ctx, &volume_server_pb.VolumeCopyRequest{ VolumeId: volumeInfo.Id, SourceDataNode: sourceNode.dataNode.Id, }) return replicateErr }) if err != nil { return err } // adjust free volume count dst.dataNode.FreeVolumeCount-- keepDataNodesSorted(allLocations) break } } if !foundNewLocation { fmt.Fprintf(writer, "failed to place volume %d replica as %s, existing:%+v\n", volumeInfo.Id, replicaPlacement, locations) } } return nil } func keepDataNodesSorted(dataNodes []location) { sort.Slice(dataNodes, func(i, j int) bool { return dataNodes[i].dataNode.FreeVolumeCount > dataNodes[j].dataNode.FreeVolumeCount }) } func satisfyReplicaPlacement(replicaPlacement *super_block.ReplicaPlacement, existingLocations []location, possibleLocation location) bool { existingDataCenters := make(map[string]bool) existingRacks := make(map[string]bool) existingDataNodes := make(map[string]bool) for _, loc := range existingLocations { existingDataCenters[loc.DataCenter()] = true existingRacks[loc.Rack()] = true existingDataNodes[loc.String()] = true } if replicaPlacement.DiffDataCenterCount >= len(existingDataCenters) { // check dc, good if different from any existing data centers _, found := existingDataCenters[possibleLocation.DataCenter()] return !found } else if replicaPlacement.DiffRackCount >= len(existingRacks) { // check rack, good if different from any existing racks _, found := existingRacks[possibleLocation.Rack()] return !found } else if replicaPlacement.SameRackCount >= len(existingDataNodes) { // check data node, good if different from any existing data nodes _, found := existingDataNodes[possibleLocation.String()] return !found } return false } type location struct { dc string rack string dataNode *master_pb.DataNodeInfo } func newLocation(dc, rack string, dataNode *master_pb.DataNodeInfo) location { return location{ dc: dc, rack: rack, dataNode: dataNode, } } func (l location) String() string { return fmt.Sprintf("%s %s %s", l.dc, l.rack, l.dataNode.Id) } func (l location) Rack() string { return fmt.Sprintf("%s %s", l.dc, l.rack) } func (l location) DataCenter() string { return l.dc }