ST6140 - MirrorCopy questions
We study ST6140 MirrorCopy capability. It allows to create mirror volume pairs using built-in tools.
We have discovered two serious drawbacks of LSI MirrorCopy:
1) It is impossible to place MirrorCopy into "suspended state". We can make one volume to be copied to mirror one in realtime, or to stop the copy process completely;
2) After we restore the mirror, the full copy process is taking place. It is long, and the main volume is closed for writes. It means that many applcation must be stopped during that process.
Those issues does not allow to implement full-scale backup system which can create backups without stopping mission-critical applications. Are those drawbacks unavoidable? Storage systems made by HDS allows to suspend copy process temporarely, do not freeze main volume during initial copy process and allow to temporarely suspend a pair with copying only changed data blocks after the mirror is restoerd.
Maybe we do something wrong?
