<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 TRANSITIONAL//EN"> <HTML> <HEAD> <META HTTP-EQUIV="Content-Type" CONTENT="text/html; CHARSET=UTF-8"> <META NAME="GENERATOR" CONTENT="GtkHTML/3.28.3"> </HEAD> <BODY> >From time to time I get this Cron Daemon warning message in root's mail fussing about a local 2.2TB RAID5 array: <BLOCKQUOTE> WARNING: mismatch_cnt is not 0 on /dev/md0 </BLOCKQUOTE> Whenever this appears I run: <BLOCKQUOTE> # echo check > /sys/block/md0/md/sync_action </BLOCKQUOTE> Followed about 24 hours later by: <BLOCKQUOTE> # cat /sys/block/md0/md/mismatch_cnt </BLOCKQUOTE> This is usually 0, so I'm happy -- until the next time the warning message appears. Two questions: 1. How can I prevent this condition from reappearing? 2. Is there a faster way to fix it? Disk I/O really bogs down while sync_action=check is running. --Doc Savage Fairview Heights, IL </BODY> </HTML>