From: Subranshu Patel Subject: Recovery and Journalling Date: Sun, 17 Mar 2013 17:37:14 +0530 Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 To: linux-ext4@vger.kernel.org Return-path: Received: from mail-qe0-f49.google.com ([209.85.128.49]:59363 "EHLO mail-qe0-f49.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755911Ab3CQMHP (ORCPT ); Sun, 17 Mar 2013 08:07:15 -0400 Received: by mail-qe0-f49.google.com with SMTP id 1so2774763qec.22 for ; Sun, 17 Mar 2013 05:07:14 -0700 (PDT) Sender: linux-ext4-owner@vger.kernel.org List-ID: This question is related to recovery (fsck and xfs_repair) and journalling. I powered off (improper shut down) the system when the IO was undergoing on mounted EXT4 filesystem. After that I powered on my machine and then used fsck on the unmounted filesystem. fsck recovered it. There are 2 things which I want to confirm: 1. Firstly fsck replays the journal for any unfinished inconsistent writes. 2. Secondly it checks/repairs the other filesystem corruption. Correct my understanding if wrong. Consider the above scenario for XFS as well. In XFS, i need to mount the filesystem, and this automatically replays the journal. After this I again unmount the filesystem and run xfs_repair. But in EXT4, i have to run fsck mandatorily before mounting my filesystem. Please confirm my understanding.