From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f171.google.com ([209.85.223.171]:35324 "EHLO mail-io0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754137AbbHFLNQ (ORCPT ); Thu, 6 Aug 2015 07:13:16 -0400 Received: by iodd187 with SMTP id d187so77360577iod.2 for ; Thu, 06 Aug 2015 04:13:15 -0700 (PDT) Subject: Re: BTRFS disaster (of my own making). Is this recoverable? To: Chris Murphy , Btrfs BTRFS References: <20150803152835.GF14352@carfax.org.uk> Cc: Hugo Mills From: Austin S Hemmelgarn Message-ID: <55C3413D.6010202@gmail.com> Date: Thu, 6 Aug 2015 07:13:01 -0400 MIME-Version: 1.0 In-Reply-To: Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-512; boundary="------------ms080100070004000502050709" Sender: linux-btrfs-owner@vger.kernel.org List-ID: This is a cryptographically signed message in MIME format. --------------ms080100070004000502050709 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable On 2015-08-05 22:13, Chris Murphy wrote: > On Wed, Aug 5, 2015 at 6:45 PM, Paul Jones wrote= : >> Would it be possible to store this type of critical information twice = on each disk, at the beginning and end? I thought BTRFS already did that,= but I might be thinking of some other filesystem. I've had my share of t= hese types of oops! moments as well. > > That option is metadata profile raid1. To do an automatic > -mconvert=3Draid1 when the user does 'btrfs device add' breaks any use > case where you want to temporarily add a small device, maybe a USB > stick, and now hundreds of MiBs possibly GiBs of metadata have to be > copied over to this device without warning. It could be made smart, > autoconvert to raid1 when the added device is at least 4x the size of > metadata allocation, but then that makes it inconsistent. OK so it > could be made interactive, but now that breaks scripts. So... where do > you draw the line? > > Maybe this would work if the system chunk only was raid1? I don't know > what the minimum necessary information is for such a case. > > Possibly it make more sense if 'btrfs device add' always does > -dconvert=3Draid1 unless a --quick option is passed? > Perhaps we could print out a big noisy warning that could be silenced? --------------ms080100070004000502050709 Content-Type: application/pkcs7-signature; name="smime.p7s" Content-Transfer-Encoding: base64 Content-Disposition: attachment; filename="smime.p7s" Content-Description: S/MIME Cryptographic Signature MIAGCSqGSIb3DQEHAqCAMIACAQExDzANBglghkgBZQMEAgMFADCABgkqhkiG9w0BBwEAAKCC Brgwgga0MIIEnKADAgECAgMQblUwDQYJKoZIhvcNAQENBQAweTEQMA4GA1UEChMHUm9vdCBD QTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNp Z25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2VydC5vcmcwHhcN MTUwMzI1MTkzNDM4WhcNMTUwOTIxMTkzNDM4WjBjMRgwFgYDVQQDEw9DQWNlcnQgV29UIFVz ZXIxIzAhBgkqhkiG9w0BCQEWFGFoZmVycm9pbjdAZ21haWwuY29tMSIwIAYJKoZIhvcNAQkB FhNhaGVtbWVsZ0BvaGlvZ3QuY29tMIICIjANBgkqhkiG9w0BAQEFAAOCAg8AMIICCgKCAgEA nQ/81tq0QBQi5w316VsVNfjg6kVVIMx760TuwA1MUaNQgQ3NyUl+UyFtjhpkNwwChjgAqfGd LIMTHAdObcwGfzO5uI2o1a8MHVQna8FRsU3QGouysIOGQlX8jFYXMKPEdnlt0GoQcd+BtESr pivbGWUEkPs1CwM6WOrs+09bAJP3qzKIr0VxervFrzrC5Dg9Rf18r9WXHElBuWHg4GYHNJ2V Ab8iKc10h44FnqxZK8RDN8ts/xX93i9bIBmHnFfyNRfiOUtNVeynJbf6kVtdHP+CRBkXCNRZ qyQT7gbTGD24P92PS2UTmDfplSBcWcTn65o3xWfesbf02jF6PL3BCrVnDRI4RgYxG3zFBJuG qvMoEODLhHKSXPAyQhwZINigZNdw5G1NqjXqUw+lIqdQvoPijK9J3eijiakh9u2bjWOMaleI SMRR6XsdM2O5qun1dqOrCgRkM0XSNtBQ2JjY7CycIx+qifJWsRaYWZz0aQU4ZrtAI7gVhO9h pyNaAGjvm7PdjEBiXq57e4QcgpwzvNlv8pG1c/hnt0msfDWNJtl3b6elhQ2Pz4w/QnWifZ8E BrFEmjeeJa2dqjE3giPVWrsH+lOvQQONsYJOuVb8b0zao4vrWeGmW2q2e3pdv0Axzm/60cJQ haZUv8+JdX9ZzqxOm5w5eUQSclt84u+D+hsCAwEAAaOCAVkwggFVMAwGA1UdEwEB/wQCMAAw VgYJYIZIAYb4QgENBEkWR1RvIGdldCB5b3VyIG93biBjZXJ0aWZpY2F0ZSBmb3IgRlJFRSBo ZWFkIG92ZXIgdG8gaHR0cDovL3d3dy5DQWNlcnQub3JnMA4GA1UdDwEB/wQEAwIDqDBABgNV HSUEOTA3BggrBgEFBQcDBAYIKwYBBQUHAwIGCisGAQQBgjcKAwQGCisGAQQBgjcKAwMGCWCG SAGG+EIEATAyBggrBgEFBQcBAQQmMCQwIgYIKwYBBQUHMAGGFmh0dHA6Ly9vY3NwLmNhY2Vy dC5vcmcwMQYDVR0fBCowKDAmoCSgIoYgaHR0cDovL2NybC5jYWNlcnQub3JnL3Jldm9rZS5j cmwwNAYDVR0RBC0wK4EUYWhmZXJyb2luN0BnbWFpbC5jb22BE2FoZW1tZWxnQG9oaW9ndC5j b20wDQYJKoZIhvcNAQENBQADggIBABr5e8W+NiTER+Q/7wiA2LxWN3UdhT3eZJjqqSlP370P KL5iWqeTfxQ67Ai/mHbJcT2PgAJ+/D2Ji+aRR03UWnU/vtOwzyDLUMstqnfl0Zs+sz/CJe7x nBA5jlpjC2DKuMVfbPze7eySaen7XSGFHKE1QoVIIpQ2kVjC4nbbJQnUbAVX1Iz29WxeVGt9 XYigz3tDPf3tglN+q23E7YjQl4abTIoM7i98yV1H9gfY8lFfKZ6jREB9+n6ie2EwS3Kat2mG tl2wBx4MfRnoSQSKsLKQ5oTwhWf0JqlFwpLfl374p0Njcykej9/jnWG8Ks1V/AXTHqI4eyIP Mf5yMZkPv7n7LS9WWKdG4Nd38iv4T2EiAaWsmgu+r81qL5CJu9AyA0SBS4ttKf6k3e63w2Mv N9R45vpQ3QhAhfWyFxFhZN95APe3YECDG3+XIRJpRYPEtHuIsOyzI70ajF93gg/BidvqKsmV MM2ccktDMfqwZXea6zey7F8Geu9R7BqjXmG2HlNuXu7e/xnHOgXf5D3wPmnRLlBhXL1Ch97a w2KjaupjpAHfFjv5kGnZXN87UvvlwzIZiKXwa3vTDwK+rrKn/sHPkfDZPSiyt/ZBIK6lX83P 34H/CzGg+Kx57rHYOIHGumIvpDa5vfWp8O0sGgawb1C2Aae4sTUVIWmIjVuGI062MYIE0TCC BM0CAQEwgYAweTEQMA4GA1UEChMHUm9vdCBDQTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNl cnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNpZ25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcN AQkBFhJzdXBwb3J0QGNhY2VydC5vcmcCAxBuVTANBglghkgBZQMEAgMFAKCCAiEwGAYJKoZI hvcNAQkDMQsGCSqGSIb3DQEHATAcBgkqhkiG9w0BCQUxDxcNMTUwODA2MTExMzAxWjBPBgkq hkiG9w0BCQQxQgRAtSK8K+5yucZ61SiEKhno9MstsFsUWC1NjqJAAyJEFxt1UWKp0ncoB9cD A0YfmOPj/sNRLWn5QUpYwoql4iBjejBsBgkqhkiG9w0BCQ8xXzBdMAsGCWCGSAFlAwQBKjAL BglghkgBZQMEAQIwCgYIKoZIhvcNAwcwDgYIKoZIhvcNAwICAgCAMA0GCCqGSIb3DQMCAgFA MAcGBSsOAwIHMA0GCCqGSIb3DQMCAgEoMIGRBgkrBgEEAYI3EAQxgYMwgYAweTEQMA4GA1UE ChMHUm9vdCBDQTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlD QSBDZXJ0IFNpZ25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2Vy dC5vcmcCAxBuVTCBkwYLKoZIhvcNAQkQAgsxgYOggYAweTEQMA4GA1UEChMHUm9vdCBDQTEe MBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNpZ25p bmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2VydC5vcmcCAxBuVTAN BgkqhkiG9w0BAQEFAASCAgAC+oMzIwsOuIuOBg1X9BlgLALlAb8rF9181z1boWtKMKb9jdfL qScCbKN2WdW0bD1RTQu0vHOhJx3dmKcD0DR5wXaVbsmGHbCbl9QVR8LqzuudmnWZgoG3E6s7 Ggm3ui6/ZZeXPGgrhO7YcIMj1heLGfmvO2dPKXGtA1lATRzfdbwtzKVvymLb8AWwF36+8/1J hGaIqvDdkoPTzvqXn9LcOslDD2NI9vKkBbMVoGOKweVHHMJF7T1VWoH1thocS25H0DULuxQ6 Z+/wspALq2EYMwuUd1JVtcTrTD2oIStOAU1I+CczKKNg4Pir35fWdInpeBHlggabidueKNMH 7LFZQhwHDiEleMVu0fgLSOTygS9pWqYu347ZobMGUcTeJg9TJczv91BqERbg75rmumWv2gi8 SjyQlf86fjXd1sx+do4tfrTMXrFfYcWooSku9kTokDSy2fhSOFH6egUyFZZoT0DwJvpOYqAs 0+g7ipwQRbeMrBfMZzNVfSYXtVVLS2z652LAxz/8j1AAtSFKBe5C9HltwjtIlssgVoZKApbb UdWiREh+2OYwQOk2e5gFPkpM7gS5LcD42wNut7DMY+aoC6rvc7KzAJ92ODfOszcti/MUzhmg BNbIg/nfjyCgOeolKIQU59z5ZYAvfUx9cghx0yJ+9Cko77SqIAIl35tpAwAAAAAAAA== --------------ms080100070004000502050709--