Skip to main content
NetApp Knowledge Base

How to run Wafliron with Iron Optional Commit (IOC)

Last Updated:

Applies to

  • ONTAP 9


Note: For full details on using this option contact NetApp Technical Support or your service provider and refer to this article.  

Wafliron with Iron Optional Commit:

  • Can only be run on non-root aggregates and Traditional volumes.
  • Doesn't allow client access until the Wafliron is complete and ready for changes to be committed/rejected.
  • Marks the aggregate offline if Wafliron is aborted or the changes are committed or rejected.
  • Breaks SnapMirror or SnapVault relationships when changes are committed.
  • Status file volume or root volume must have "guarantee=volume" set before starting the Wafliron.
  • Requires a volume large enough to hold the status files during the Wafliron or it will abort.

Root Aggregate size

Small root aggregates (1 - 2 data disks) may become disk-bound if a high number of writes are needed to the changelog file. If the disks become a bottleneck, IOC run times will be extremely long. Increase the number of data disks in the root aggregate or create a temporate status file volume:  How to create a temporary volume for Wafliron status files.

Additional Information

  • Status files used by wafliron optional commit are stored in the storage system's root volume, and any blocks fixed will be redirected to these status files. The status files are space reserved and automatically sized to approximately 120% of system memory.




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.


  • Was this article helpful?