Add max number of volumes that can be attached to an instance

pkg/driver/node.go

@@ -44,6 +44,10 @@ const (
 
 	// default file system type to be used when it is not provided
 	defaultFsType = FSTypeExt4
+
+	// maxVolumesPerNode is the maximum number of volumes that an AWS instance can have attached.
+	// More info at https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/volume_limits.html
+	maxVolumesPerNode = 39
 )
 
 var (
@@ -316,6 +320,7 @@ func (d *nodeService) NodeGetInfo(ctx context.Context, req *csi.NodeGetInfoReque
 
 	return &csi.NodeGetInfoResponse{
 		NodeId:             m.GetInstanceID(),
+		MaxVolumesPerNode:  maxVolumesPerNode,
 		AccessibleTopology: topology,
 	}, nil
 }

pkg/driver/node_test.go

@@ -767,7 +767,8 @@ func TestNodeGetInfo(t *testing.T) {
 	awsDriver := newTestNodeService(mockMetadata, NewFakeMounter())
 
 	expResp := &csi.NodeGetInfoResponse{
-		NodeId: expInstanceId,
+		NodeId:            expInstanceId,
+		MaxVolumesPerNode: maxVolumesPerNode,
 		AccessibleTopology: &csi.Topology{
 			Segments: map[string]string{TopologyKey: mockMetadata.GetAvailabilityZone()},
 		},