Hello everyone! What does following error mean, I am getting this in /var/log/messages repeatedly, this morning my server (IBM eServer x226) was unable to boot and when it booted its giving following errors. I have RAID 1 (Adaptec HOSTRAID) setup on this server. How to fix this? "fdisk -l /dev/sdb" does not give me any output. Yesterday I had power failure (UPS failure) and server shutdown abruptly. Mar 23 12:11:53 matrix kernel: sd 3:0:0:0: Device not ready: <6>: Current: sense key: Not Ready Mar 23 12:11:53 matrix kernel: Add. Sense: Logical unit not ready, initializing command required Mar 23 12:11:53 matrix kernel: Mar 23 12:11:53 matrix kernel: end_request: I/O error, dev sdb, sector 0 Mar 23 12:11:53 matrix kernel: Buffer I/O error on device sdb, logical block 0 Mar 23 12:11:53 matrix kernel: Buffer I/O error on device sdb, logical block 1 Mar 23 12:11:53 matrix kernel: Buffer I/O error on device sdb, logical block 2 Mar 23 12:11:53 matrix kernel: sd 3:0:0:0: Device not ready: <6>: Current: sense key: Not Ready If I run smartctl, I get following: [root at matrix ~]# smartctl -a /dev/sdb Device: IBM-ESXS PYH300C3-ETS10FN Version: RXQN Serial number: VAVH8YVA Device type: disk Local Time is: Fri Mar 23 12:23:53 2012 IST *device is NOT READY (e.g. spun down, busy)* A mandatory SMART command failed: exiting. To continue, add one or more '-T permissive' options. -- Without Wax! Rahul Tidke