<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN"> <HTML> <HEAD> <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=us-ascii"> <META NAME="Generator" CONTENT="MS Exchange Server version 6.5.7652.24"> <TITLE>Activate/rebuilding with broken disk</TITLE> </HEAD> <BODY>  Hi, I'm writing code to make data recovery (rebuild) with dmraid/device-mapper. Assume I have created and mounted a mirror raid volume with disk A and B. # dmsetup table isw_dgdccjfdbi_test: 0 20971779 mirror core 2 16384 nosync 2 8:16 0 8:32 0 1 handle_errors # dmsetup status isw_dgdccjfdbi_test: 0 20971779 mirror 2 8:16 8:32 1281/1281 1 AA 1 core When I remove one of disk (assume A) and make write or read from that volume I receive dmsetup status with one "AD" (with appropriate patches to kernel). I can work with one broken disk (assume it is mirror) and device-mapper will take care of next writes/reads to be directed only to device B. Then I add a new disk C (for example 8:48). Some questions I have: 1. How to update device mapper table in a way where device-mapper will know that I have only disk B and C and that C is a new empty disk that should not be used at the moment? 2. If 1 is possible without interrupting system work (volume is still mounted) then is it possible to start rebuilding of disk B to C (also with mounted volume)? 3. During rebuild "dmsetup status" will show rebuild progress from 0//1281 to 1281/1281 - assume it is in the middle 500/1281 A) Does device mapper take care of writes to disk B and C together if they are directed to blocks just recovered? B) Does device mapper take care of writes only to disk B if they are directed to blocks not recovered yet? Regards, Radoslaw Mitura <pre>--------------------------------------------------------------------- Intel Technology Poland sp. z o.o. z siedziba w Gdansku ul. Slowackiego 173 80-298 Gdansk Sad Rejonowy Gdansk Polnoc w Gdansku, VII Wydzial Gospodarczy Krajowego Rejestru Sadowego, numer KRS 101882 NIP 957-07-52-316 Kapital zakladowy 200.000 zl This e-mail and any attachments may contain confidential material for the sole use of the intended recipient(s). Any review or distribution by others is strictly prohibited. If you are not the intended recipient, please contact the sender and delete all copies. </pre></BODY> </HTML>