From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kit Westneat Subject: Buffer I/O error Date: Fri, 24 Oct 2008 15:22:32 -0400 Message-ID: <49022078.6010700@datadirectnet.com> Reply-To: device-mapper development Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: dm-devel@redhat.com List-Id: dm-devel.ids Hi dm-devel, I'm running into an issue with dm-multipath (device-mapper-multipath-0.4.5-27.el4_6.3) that has me confused and I was hoping I could get some guidance. Here are the relevant dmesg messages: device-mapper: dm-multipath: Failing path 8:48. device-mapper: dm-multipath: Failing path 8:48. device-mapper: dm-multipath: Failing path 8:48. device-mapper: dm-multipath: Failing path 65:80. printk: 1004 messages suppressed. Buffer I/O error on device dm-13, logical block 1192525829 lost page write due to I/O error on dm-13 Normally when I have seen Buffer I/O errors in the past, they have been accompanied by SCSI errors as well, but in this case I am not getting anything. One odd thing is that the filesystem reported extremely slow writes before the buffer I/O errors occurred. I have checked and double-checked the storage array and everything seems fine. I am using directio as my path checker if that makes a difference. I have been able to reproduce the problem consistently by attempting an fsck on dm-13. However, I am now doing an fsck on the underlying sd device and it hasn't bombed out yet with the buffer I/O errors. Has anyone encountered these seemingly inexplicable buffer I/O errors before? Any advice on how to debug it? Thanks, Kit Westneat