similar to: interaction with hardware RAID?

I created a 1TB RAID1. So far it is just for testing, no important data on there. After a reboot, I tried to mount it again # mount /dev/mapper/vg00-btrfsvol0_0 /mnt/btrfs0 mount: wrong fs type, bad option, bad superblock on /dev/mapper/vg00-btrfsvol0_0, missing codepage or helper program, or other error In some cases useful info is found in syslog - try dmesg | tail or

I notice this question on the wiki/faq: https://btrfs.wiki.kernel.org/index.php/UseCases#What_is_best_practice_when_partitioning_a_device_that_holds_one_or_more_btr-filesystems and as it hasn''t been answered, can anyone make any comments on the subject Various things come to mind: a) partition the disk, create an LVM partition, and create lots of small LVs, format each as btrfs b)

The Wiki does not make it clear as to why adding a secondary device defaults to RAID1 metadata and RAID0 data. I bought two SSDs with the intention of doing a BTRFS RAID0 for my root. What is the difference between forcing RAID0 on metadata and data as opposed to the default behavior? Can anyone clarify that? Thank you for your time, Mario -- To unsubscribe from this list: send the line

Did something break.. ? we are not reporting raid type after balance. ----------- # btrfs fi df /btrfs Data, RAID0: total=2.00GB, used=2.03MB Data: total=8.00MB, used=0.00 System, RAID0: total=16.00MB, used=4.00KB System: total=4.00MB, used=0.00 Metadata, RAID0: total=2.00GB, used=216.00KB Metadata: total=8.00MB, used=4.00KB # btrfs bal /btrfs Done, had to relocate 5 out of 5 chunks # btrfs fi

Hi! I recently tried to mount a filesystem in RAID1 mode using loopback devices. I followed the instructions at [1]. Here''s exactly what I''ve done: $ dd if=/dev/zero of=raid1_0.img bs=1M count=500 $ dd if=/dev/zero of=raid1_1.img bs=1M count=500 $ mkfs.btrfs -m raid1 -d raid1 raid1_0.img raid1_1.img $ losetup /dev/loop0 raid1_0.img $ losetup /dev/loop1 raid1_1.img $ mount -t

Hello, I am on Ubuntu Server 13.04 with Linux 3.8. I''ve created a "single-raid" using /dev/sd{a,b,c,d}{1,3}. One of my hard drives has failed, I mean it''s materially dead. :~$ sudo btrfs filesystem show Label: none uuid: 40886f51-8c9b-4be1-8721-83bf5653d2a0 Total devices 5 FS bytes used 226.90GB devid 4 size 37.27GB used 31.01GB path /dev/sdd1

If we''ve abandoned the idea of putting the number of redundant blocks into the top bits of the type bitmask (and I hope we have), then we''re fairly much there. Current code is at: git://, http://git.infradead.org/users/dwmw2/btrfs-raid56.git git://, http://git.infradead.org/users/dwmw2/btrfs-progs-raid56.git We have recovery working, as well as both full-stripe writes

Hi. I''m considering an imminent switch from ext4 to btrfs and I''m hoping that someone can lend me advice before I do something unsupported. I have a software raid 6 array configured via mdadm. It was sitting at 8 x 3TB until I recently doubled that, grew the array and found that ext4 doesn''t want to resize. So, I''m looking to: 1. convert from ext4 to btrfs

We discussed using the top bits of the chunk type field field to store a number of redundant disks -- so instead of RAID5, RAID6, etc., we end up with a single ''RAID56'' flag, and the amount of redundancy is stored elsewhere. This attempts it, but I hate it and don''t really want to do it. The type field is designed as a bitmask, and _used_ as a bitmask in a number of

Hi, I have added 2x2Tb to my existing 2x2Tb raid 1 btrfs filesystem and then ran a balance: # btrfs filesystem show Total devices 4 FS bytes used 1.74TB devid 3 size 1.82TB used 0.00 path /dev/sdd devid 4 size 1.82TB used 0.00 path /dev/sde devid 2 size 1.82TB used 1.75TB path /dev/sdc devid 1 size 1.82TB used 1.75TB path /dev/sdb # btrfs

Greetings, I have a few questions pertaining to BTRFS RAID. I know it''s been rumored a lot recently that kernel 3.4 will have RAID5/6 support, is this still the case. Also, is it possible to change from a single drive system to a raid system or even a multi drive system without raid to a raid system while there is data on the drives an successfully convert them without loosing data?

Hi folks, For people who might be interested, here is how btrfs performs with two partitions on a single SSD drive in a RAID-1 mirror. This is on a Dell E4200 with Core 2 Duo U9300 (1.2GHz), 2GB RAM and a Samsung SSD (128GB Thin uSATA SSD). Version 1.03c ------Sequential Output------ --Sequential Input- --Random- -Per Chr- --Block-- -Rewrite- -Per Chr- --Block--

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 I''ve been unable to find anything definitive about what happens if I use RAID0 to join an SSD and HDD together with respect to performance (latency, throughput). The future is obvious (hot data tracking, using most appropriate device for the data, data migration). In my specific case I have a 250GB SSD and a 500GB HDD, and about 250GB of

Hello everyone, Btrfs v0.16 is available for download, please see http://btrfs.wiki.kernel.org/ for download links and project information. v0.16 has a shiny new disk format, and is not compatible with filesystems created by older Btrfs releases. But, it should be the fastest Btrfs yet, with a wide variety of scalability fixes and new features. There were quite a few contributors this time

Is there a way to mix RAID 1 and 0 in different subvolumes? I am a new user to btrfs and would like to protect the important files with mirroring, but have a bulk area that is striped for speed and size. For example I want / and /home to be mirrored, but /media can just be striped as it is all data I can easily recreate. I see an item in the Project_ideas wiki entry called "Online raid

I came across the tidbit that ZFS has a contract guarantee that the data read back will either be correct (the checksum computed over the data read from the disk matches the checksum stored on disk), or you get an I/O error. Obviously, this greatly reduces the probability that the data is invalid. (Particularly when taken in combination with the disk firmware''s own ECC and checksumming.)

Dear all, While going through the archived mailing list and crawling along the wiki I didn''t find any clues if there would be any optimizations in Btrfs to make efficient use of functions and features that today exist on enterprise class storage arrays. One exception to that was the ssd option which I think can make a improvement on read and write IO''s however when attached to

I''ve run a little wired benchmark on comparing Btrfs v0.19 and XFS: There are 2000 directories and each directory contains 1000 files. The workload randomly stat a file or chmod a file for 2000000 times. And the number of stat and chmod are 50% and 50%. I monitor the number of disk read requests #Disk Write Requests, #Disk Read Requests, #Disk Write Sectors, #Disk Read

Hello, Trying to put together a list of TODO items for btrfs so we can update the wiki page fully. So far these things are on the list * Proper ENOSPC handling * O_DIRECT support (without checksumming) * AIO support * Subvolume quotas and inherited space usage information * Snapshot removal * QA Suite for automated regression testing * Reserved space for online fsck and the ability to add

I''m currently researching an upgrade to (raid1-ed) btrfs from mostly reiserfs (which I''ve found quite reliable (even thru a period of bad ram and resulting system crashes) since data=ordered went in with 2.6.16 or whatever it was. (Thanks, Chris! =:^)) on multiple md/raid-1s. I have some questions that don''t appear to be addressed well on the wiki, yet, or where