I have a couple computers running 2.6.38 (Ubuntu Natty 2.6.38-8-generic), and on both of them "btrfs device scan" comes back with nothing other than "failed to read /dev/sr0" One computer has a btrfs RAID-1 volume, and the other has two separate btrfs filesystems. The results are the same whether the filesystems are mounted or not. Why is "btrfs device scan" not scanning the devices? vic -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hallo, Victor, Du meintest am 12.05.11:> I have a couple computers running 2.6.38 > (Ubuntu Natty 2.6.38-8-generic), and on both of them > "btrfs device scan" comes back with nothing other than > "failed to read /dev/sr0"> One computer has a btrfs RAID-1 volume, and the other has two > separate btrfs filesystems. The results are the same whether the > filesystems are mounted or not.What tells ls /dev/sd* ls /dev/md*> Why is "btrfs device scan" not scanning the devices?If I have understood the scan routine then it looks for all (?) block devices in "/dev". Viele Gruesse! Helmut -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 05/12/2011 12:46 PM, Helmut Hullen wrote:> Hallo, Victor, > > Du meintest am 12.05.11: > >> I have a couple computers running 2.6.38 >> (Ubuntu Natty 2.6.38-8-generic), and on both of them >> "btrfs device scan" comes back with nothing other than >> "failed to read /dev/sr0" > > What tells > > ls /dev/sd* > ls /dev/md*$ ls /dev/sd* /dev/sda /dev/sda1 /dev/sda2 /dev/sda5 /dev/sdb /dev/sdb1 /dev/sdc /dev/sdc1 $ ls /dev/md* ls: cannot access /dev/md*: No such file or directory $ btrfs device scan Scanning for Btrfs filesystems failed to read /dev/sr0 $ btrfs filesystem show failed to read /dev/sr0 Label: ''server-backup'' uuid: b927ead9-2e5b-4ee8-b9f4-7209177c49d8 Total devices 2 FS bytes used 603.17GB devid 1 size 1.36TB used 605.28GB path /dev/sdb1 devid 2 size 1.36TB used 605.26GB path /dev/sdc1 Btrfs Btrfs v0.19 $ -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 12.05.2011 06:26, Victor Roetman wrote:> I have a couple computers running 2.6.38 > (Ubuntu Natty 2.6.38-8-generic), and on both of them > "btrfs device scan" comes back with nothing other than > "failed to read /dev/sr0" > > One computer has a btrfs RAID-1 volume, and the other has two separate > btrfs filesystems. The results are the same whether the filesystems are > mounted or not. > > Why is "btrfs device scan" not scanning the devices?Normally it does not report anything to stdout/stderr. You can see the scan result in dmesg. -Arne> > vic > -- > To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html-- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hallo, Victor, Du meintest am 12.05.11:>>> I have a couple computers running 2.6.38 >>> (Ubuntu Natty 2.6.38-8-generic), and on both of them >>> "btrfs device scan" comes back with nothing other than >>> "failed to read /dev/sr0"[..]> $ btrfs device scan > Scanning for Btrfs filesystems > failed to read /dev/sr0That''s a "well known" error; "scan" tries block devices which really cannot contain a btrfs filesystem. People who don''t use "udev" get a lot of more "failed to read" messages; "scan" seems to try every block device which exists in "/dev". Maybe it''s more reliable if "scan" doesn''t look into "dev" but uses "/ proc/partitions".> $ btrfs filesystem show > failed to read /dev/sr0 > Label: ''server-backup'' uuid: b927ead9-2e5b-4ee8-b9f4-7209177c49d8 > Total devices 2 FS bytes used 603.17GB > devid 1 size 1.36TB used 605.28GB path /dev/sdb1 > devid 2 size 1.36TB used 605.26GB path /dev/sdc1That shows that (in this case) you can ignore the "scan" message. Viele Gruesse! Helmut -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html