From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-io0-f172.google.com ([209.85.223.172]:35971 "EHLO mail-io0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752794AbbHZLmN (ORCPT ); Wed, 26 Aug 2015 07:42:13 -0400 Received: by iodv127 with SMTP id v127so14795219iod.3 for ; Wed, 26 Aug 2015 04:42:12 -0700 (PDT) Subject: Re: Understanding BTRFS storage To: George Duffield , linux-btrfs@vger.kernel.org References: From: Austin S Hemmelgarn Message-ID: <55DDA603.9020507@gmail.com> Date: Wed, 26 Aug 2015 07:41:55 -0400 MIME-Version: 1.0 In-Reply-To: Content-Type: multipart/signed; protocol="application/pkcs7-signature"; micalg=sha-512; boundary="------------ms030903020700070509060006" Sender: linux-btrfs-owner@vger.kernel.org List-ID: This is a cryptographically signed message in MIME format. --------------ms030903020700070509060006 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: quoted-printable On 2015-08-26 04:56, George Duffield wrote: > Hi > > Is there a more comprehensive discussion/ documentation of Btrfs > features than is referenced in > https://btrfs.wiki.kernel.org/index.php/Main_Page...I'd love to learn > more but it seems there's no readily available authoritative > documentation out there? > > I'm looking to switch from a 5x3TB mdadm raid5 array to a Btrfs based > solution that will involve duplicating a data store on a second > machine for backup purposes (the machine is only powered up for > backups). > > Two quick questions: > - If I were simply to create a Btrfs volume using 5x3TB drives and not > create a raid5/6/10 array I understand data would be striped across > the 5 drives with no reduncancy ... i.e. if a drive fails all data is > lost? Is this correct? Yes, although the striping is at a much larger granularity than a=20 typical RAID0. > > - Is Btrfs RAID10 (for data) ready to be used reliably? Yes, in general it is. --------------ms030903020700070509060006 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 hvcNAQkDMQsGCSqGSIb3DQEHATAcBgkqhkiG9w0BCQUxDxcNMTUwODI2MTE0MTU1WjBPBgkq hkiG9w0BCQQxQgRAJml2c/mwXhK/MeLHBlQaKfaVh1yagg1ZWjGjxyGnO6dm02+Qaln16pnl gSMiTRJGRNBkPGFotaC7dZcawpbV/DBsBgkqhkiG9w0BCQ8xXzBdMAsGCWCGSAFlAwQBKjAL BglghkgBZQMEAQIwCgYIKoZIhvcNAwcwDgYIKoZIhvcNAwICAgCAMA0GCCqGSIb3DQMCAgFA MAcGBSsOAwIHMA0GCCqGSIb3DQMCAgEoMIGRBgkrBgEEAYI3EAQxgYMwgYAweTEQMA4GA1UE ChMHUm9vdCBDQTEeMBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlD QSBDZXJ0IFNpZ25pbmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2Vy dC5vcmcCAxBuVTCBkwYLKoZIhvcNAQkQAgsxgYOggYAweTEQMA4GA1UEChMHUm9vdCBDQTEe MBwGA1UECxMVaHR0cDovL3d3dy5jYWNlcnQub3JnMSIwIAYDVQQDExlDQSBDZXJ0IFNpZ25p bmcgQXV0aG9yaXR5MSEwHwYJKoZIhvcNAQkBFhJzdXBwb3J0QGNhY2VydC5vcmcCAxBuVTAN BgkqhkiG9w0BAQEFAASCAgBQqjbr/0E3jHvauFVT3Sjw5Co3Of91Bmg6HXH8bpVLMiMs69pA l/SXHtonnDB23xxMNx5qzGsnA0a87oVUOaRC2NWIZjyULI4oNdapFVyCi0Ssf72gi04NzD6J YXtDIewj5T03W9lhI5sknbpa+gHE0tkt/Y9i+0ET5tQCIq1J5cHULKqEHK2gUEeAGIenh5zy OXycwDmz4aLk6ceeESN44Ae9MJA93ZVeDw57pMNuW24R3Q9RNpB6RVN4Ej2XKiHl/rK2Lq0W LMVACTD50UCMgVoChGhCyVna6yAta9jqgk+7TjfC8WjLPvqF54eyUu/vrPZWprKQmSsYYGB9 R7PvS4E76nIyR5YvfqWaEa/hGjNHtRnrcYJOXjT5hECUAJ/08hNASfhLLF+duILTVWbsLSuG sZTNTDj6E+m3z6V7gzo3/+kBB++Jp4t2Qpv9Ww9lWhUOO4umm0LwvZHQ4kC3D5fW+8U3Q3hI OSDHKyUwjHTlszb33XOh+jIUDvzWOPK4SpvL9rxTZNJZhUD//r2G3d/YakietPY6jAAQ0ubA dqPap+gOJ3fCdbiHMK/60zAslloFX/JUrzMWdNm3b1HTrZ83An1blCLI38djWSFfb6550Xnw AVd39ZJwVnuo9DYyqigWF51yWR/lXQhGKFVVB3KoKJjCYFj6vx+iEXOtxgAAAAAAAA== --------------ms030903020700070509060006--