Disabling the change_fsid option in MetroCluster configurations

In a MetroCluster configuration, you can take advantage of the change_fsid option in Data ONTAP to simplify site takeover when the cf forcetakeover -d command is used.

In a MetroCluster configuration, if a site takeover initiated by the cf forcetakeover -d command occurs, the following happens:

  • Data ONTAP changes the file system IDs (FSIDs) of volumes and aggregates because ownership changes.
  • Because of the FSID change, clients must remount their volumes if a takeover occurs.
  • If using Logical Units (LUNs), the LUNs must also be brought back online after the takeover.

To avoid the FSID change in the case of a site takeover, you can set the change_fsid option to off (the default is on ). Setting this option to off has the following results if a site takeover is initiated by the cf forcetakeover -d command:

  • Data ONTAP refrains from changing the FSIDs of volumes and aggregates.
  • Users can continue to access their volumes after site takeover without remounting.
  • LUNs remain online.
Attention: If the option is set to off , any data written to the failed node that did not get written to the surviving node's NVRAM is lost. Disable the change_fsid option with great care.
  1. Enter the following command to disable the change_fsid option:options cf.takeover.change_fsid off By default, the change_fsid option is enabled (set to on ).