From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from [195.159.176.226] ([195.159.176.226]:50374 "EHLO blaine.gmane.org" rhost-flags-FAIL-FAIL-OK-OK) by vger.kernel.org with ESMTP id S934609AbcIPXS1 (ORCPT ); Fri, 16 Sep 2016 19:18:27 -0400 Received: from list by blaine.gmane.org with local (Exim 4.84_2) (envelope-from ) id 1bl2Og-0001w1-8d for linux-btrfs@vger.kernel.org; Sat, 17 Sep 2016 01:18:18 +0200 To: linux-btrfs@vger.kernel.org From: Duncan <1i5t5.duncan@cox.net> Subject: Re: Filesystem will remount read-only Date: Fri, 16 Sep 2016 23:18:03 +0000 (UTC) Message-ID: References: <8AC4324B47948D40A1031D5AB7D077820141E77717@mailstore.skyward.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-btrfs-owner@vger.kernel.org List-ID: Jeffrey Michels posted on Fri, 16 Sep 2016 14:57:43 +0000 as excerpted: > Hello, > > I have a system that has been in production for a few years. The SAN > the VM was running on had a hardware failure about a month ago and now > one of the two btrfs filesystems will remount after boot read-only. > Here is the system information: > > uname -a > > Linux retain 3.0.101-0.47.71-default #1 SMP Thu Nov 12 12:22:22 UTC 2015 > (b5b212e) x86_64 x86_64 x86_64 GNU/Linux > > Btrfs --version > > Btrfs v0.20+ That is positively /ancient/, both kernel and userspace (btrfs-progs). Keep in mind that btrfs was still considered very experimental back then, with the experimental labels coming off only with 3.14 or there abouts, IIRC (userspace releases got version-synced with kernelspace in 3.12, so 3.14 applies to both). So you have been running an at-the-time still extremely experimental filesystem for years now, and it's only now coming up with problems that need fixed. Pretty remarkable for the experimental state back then, but it doesn't change the fact that it /was/ "may eat your data and burn your kids alive as a sacrifice to appease the filesystem gods" level experimental, with the according warnings, back then. So first thing I'd suggest is to update to kernel 4.4 LTS series, and something similar for btrfs-progs userspace. Then, given the age and experimental nature of the filesystem back then, I'd kill the filesystems and do a fresh mkfs.btrfs, restoring from backups. That way you're starting with a well tested and stable LTS kernel that is both reasonably mature already, and will be supported for some time to come, and eliminate any possibility of long fixed and forgotten bugs coming back to bite you years later. Alternatively, if you're using a long-term support distro, you have the choice of going to them for that support, since unlike this list which focuses on the state going forward, that sort of deep long-term support of long outdated versions is a good part of the reason such distros exist, and a good part of why a lot of people are willing to pay sometimes rather sizable sums of money /for/ that level of support. -- Duncan - List replies preferred. No HTML msgs. "Every nonfree program has a lord, a master -- and if you use the program, he is your master." Richard Stallman