From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from len.romanrm.net ([195.154.117.182]:37600 "EHLO len.romanrm.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752263AbcKPLAf (ORCPT ); Wed, 16 Nov 2016 06:00:35 -0500 Date: Wed, 16 Nov 2016 16:00:31 +0500 From: Roman Mamedov To: Martin Steigerwald Cc: , Martin Subject: Re: degraded BTRFS RAID 1 not mountable: open_ctree failed, unable to find block group for 0 Message-ID: <20161116160031.59041b46@natsu> In-Reply-To: <3374757.aMVjisyVFB@merkaba> References: <18970348.FUMEOFOSb3@merkaba> <20161116154336.543a326b@natsu> <3374757.aMVjisyVFB@merkaba> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-btrfs-owner@vger.kernel.org List-ID: On Wed, 16 Nov 2016 11:55:32 +0100 Martin Steigerwald wrote: > I do think that above kernel messages invite such a kind of interpretation > tough. I took the "BTRFS: open_ctree failed" message as indicative to some > structural issue with the filesystem. For the reason as to why the writable mount didn't work, check "btrfs fi df" for the filesystem to see if you have any "single" profile chunks on it: quite likely you did already mount it "degraded,rw" in the past *once*, after which those "single" chunks get created, and consequently it won't mount r/w anymore (without lifting the restriction on the number of missing devices as proposed). -- With respect, Roman