CHKDSK Considerations

If you must run CHKDSK on a volume that is being mirrored by SIOS DataKeeper, it is recommended that you first pause the mirror. After running CHKDSK, continue the mirror. A partial resync occurs (updating those writes generated by the CHKDSK) and mirroring will continue.

Failure to first pause the mirror may result in the mirror automatically entering the Paused state and performing a Resync while CHKDSK is in operation. While this will not cause any obvious problems, it will slow the CHKDSK down and result in unnecessary state changes in SIOS DataKeeper.

SIOS DataKeeper automatically ensures that volumes participating in a mirror, as either source or target, are not automatically checked at system startup. This ensures that the data on the mirrored volumes remains consistent.

Note: The bitmap file (for non-shared volumes) is located on the C drive which is defined by BitmapBaseDir as the default location. Running CHKDSK on the C drive of the Source system will cause an error due to the active bitmap file. Therefore, a switchover must be performed so that this Source becomes Target and the bitmap file becomes inactive. The CHKDSK can then be executed on this system as the new target (original source).