Skip to main content
NetApp Knowledge Base

VAAI: What are the copy offload engines that ONTAP uses?

Last Updated:

Applies to

  • VMware vSphere APIs for Array Integration (VAAI)
  • NetApp ONTAP


Data ONTAP makes use of three copy offload engines (all part of the NFS Copy Manager Services):

SCE (known as the SisClone or System Continuous Engineering Engine)

  • This engine is used for intra-volume (i.e. within the same volume) copies only 
  • SCE leverages WAFL's SiSClone technology to copy references to existing blocks.  In other words, pointers to existing blocks are created rather than the physical blocks themselves being copied.
  • The FlexClone license is needed to make use of SCE
  • The flexvol needs to have sis enabled before SCE can be used:
    • sis on -volume <vol_name> -vserver <SVM_name>

BCE (or Block Copy Engine)

  • This engine is used for intra-volume and inter-volume copies
  • This engine performs block-for-block copies of the data
  • If the SCE engine cannot be used for intra-volume copies, than the BCE is used instead
  • BCE cannot be used between physical nodes

SpinNP Copy Engine (also refered to as SpinCE)

  • This engine is used for volume copies across physical nodes
  • This engine performs block-for-block copies of the data

Additional Information



NetApp provides no representations or warranties regarding the accuracy or reliability or serviceability of any information or recommendations provided in this publication or with respect to any results that may be obtained by the use of the information or observance of any recommendations provided herein. The information in this document is distributed AS IS and the use of this information or the implementation of any recommendations or techniques herein is a customer's responsibility and depends on the customer's ability to evaluate and integrate them into the customer's operational environment. This document and the information contained herein may be used solely in connection with the NetApp products discussed in this document.