When you end mirroring for a dbspace, blobspace, or sbspace, the database server immediately releases the mirror chunks of that space. These chunks are immediately available for reassignment to other storage spaces.
Only users informix and root on UNIX or members of the Informix-Admin group on Windows can end mirroring.
You cannot end mirroring if any of the primary chunks in the dbspace are down. The system can be in online mode when you end mirroring.
You can end mirroring with the onspaces utility. For example, to end mirroring for the root dbspace, enter the following command:
onspaces -r rootdbs
Another way to end mirroring is to select Index by Utility > onspaces > -r.
To end mirroring for a dbspace or blobspace with ON–Monitor, select the Dbspaces > Mirror option. Select a dbspace or blobspace that is mirrored and press CTRL-B or F3.