unRAID 6 Beta 6: Btrfs Quick-Start Guide


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OK, i did this... and I think I'm OK

 

 mkfs.btrfs -f -m raid1 -d raid1 -L VM-store /dev/sdf /dev/sdh /dev/sdg

 mkdir /boot/btrfs

 mount -t btrfs /dev/sdf /mnt/btrfs/

 df
Filesystem      1K-blocks   Used Available Use% Mounted on
/dev/sda1         3882752 923200   2959552  24% /boot
/dev/sdf       1465159752   1280 976753664   1% /mnt/btrfs

dd if=/dev/zero of=/mnt/btrfs/bench.test bs=1M count=2000
2000+0 records in
2000+0 records out
2097152000 bytes (2.1 GB) copied, 0.47854 s, 4.4 GB/s

blkid /dev/sdf
/dev/sdf: LABEL="VM-store" UUID="569b8d06-5676-4e2d-9a22-12d85dd1648d" UUID_SUB="bc85940f-c379-4b4f-b10d-370b6d12de3c" TYPE="btrfs"

root@tower:~# btrfs filesystem df /mnt/btrfs/
Data, RAID1: total=3.00GiB, used=1.95GiB
Data, single: total=8.00MiB, used=0.00
System, RAID1: total=8.00MiB, used=16.00KiB
System, single: total=4.00MiB, used=0.00
Metadata, RAID1: total=1.00GiB, used=2.09MiB
Metadata, single: total=8.00MiB, used=0.00
unknown, single: total=16.00MiB, used=0.00

root@tower:~# btrfs filesystem show /dev/sdf
Label: 'VM-store'  uuid: 569b8d06-5676-4e2d-9a22-12d85dd1648d
        Total devices 3 FS bytes used 1.96GiB
        devid    1 size 465.76GiB used 2.02GiB path /dev/sdf
        devid    2 size 465.76GiB used 3.01GiB path /dev/sdh
        devid    3 size 465.76GiB used 3.01GiB path /dev/sdg

btrfs filesystem show /dev/sdf
Label: 'VM-store'  uuid: 569b8d06-5676-4e2d-9a22-12d85dd1648d
        Total devices 3 FS bytes used 1.96GiB
        devid    1 size 465.76GiB used 2.02GiB path /dev/sdf
        devid    2 size 465.76GiB used 3.01GiB path /dev/sdh
        devid    3 size 465.76GiB used 3.01GiB path /dev/sdg

 

 

So what is the best way to mount this in the go file ?

using /dev/sdf looks not correct, since this might can change during boot?

 

 

//Peter

 

use "uuid: 569b8d06-5676-4e2d-9a22-12d85dd1648d" instead

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Done that already, if I want to convert to raid5? is that possible?.... going googling little about that ;-)

 

//Peter

 

Not sure, but I would think this is possible...  We will be experimenting more with this more and more in the weeks/months ahead to see what we can and can't do.

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thanks for nothing again

 

>:(

 

NO SWAP files on btrfs ??

you couldn't have put that in big letters on the first post

 

spend 4 hours moving stuff of the cache drive

reformat the thing and now swap file is not working

 

Jun 20 00:58:26 R2D2 kernel: swapon: swapfile has holes

Jun 20 00:58:26 R2D2 rc.swapfile[10796]: Swap file /mnt/cache/swapfile re-used and started

Jun 20 01:05:59 R2D2 kernel: mdcmd (55): spindown 0 (Routine)

Jun 20 01:08:34 R2D2 rc.swapfile[11875]: Swap file /mnt/cache/swapfile re-used and started

Jun 20 01:08:34 R2D2 kernel: swapon: swapfile has holes

Jun 20 01:12:50 R2D2 rc.swapfile[12244]: Creating swap file /mnt/cache/swapfile please wait ...

Jun 20 01:14:41 R2D2 rc.swapfile[12382]: Swap file /mnt/cache/swapfile created and started

Jun 20 01:14:41 R2D2 kernel: swapon: swapfile has holes

 

a google search gives conflicting info but btrfs wiki says not supported ?

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Hmmm, after a reboot i see this

root@tower:/mnt# blkid /dev/sdf
/dev/sdf: LABEL="VM-store" UUID="569b8d06-5676-4e2d-9a22-12d85dd1648d" UUID_SUB="bc85940f-c379-4b4f-b10d-370b6d12de3c" TYPE="btrfs"
root@tower:/mnt# mount /dev/disk/by-uuid/569b8d06-5676-4e2d-9a22-12d85dd1648d /mnt/vm_disk/
mount: wrong fs type, bad option, bad superblock on /dev/sdf,
       missing codepage or helper program, or other error
       In some cases useful info is found in syslog - try
       dmesg | tail  or so

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so , what's the big deal?

shrink your btrfs volume

 

add swap partition to RAW device.

 

all you guys assume we are all commandline jockeys

the things is that we have no clue how to even start at that .... we were spoiled with plugins

we assume if limetech changes a cache drive filesystem that they at least know that a lot of us are running a swapfile ....

they asked for the data in the polls

so if they change filesystem they at least need to be sure this will not affect us in any bad way

2 o clock in the morning and in 4 hours have to get up for work

and plex is still not running (plex folder = 91 GB)

 

 

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hay, hay, hay, who do you call a command line jokey :-)

 

I hate command line and almost a noob in Linux myself.

I read manuals and google the rest :-)

 

also LM did not change file system, they add support for new file system.

you do not have to use it though or at least read ahead about the new file system before using it. that what I did when rebuilding my server (not unRaid).

since I am a noob, who comes from windows through and through, it was a quest of epic proportions, so far so good...

 

 

 

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hay, hay, hay, who do you call a command line jokey :-)

 

I hate command line and almost a noob in Linux myself.

I read manuals and google the rest :-)

 

also LM did not change file system, they add support for new file system.

you do not have to use it though or at least read ahead about the new file system before using it. that what I did when rebuilding my server (not unRaid).

since I am a noob, who comes from windows through and through, it was a quest of epic proportions, so far so good...

 

NO docker without btrfs

so they force us to use it :(

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hay, hay, hay, who do you call a command line jokey :-)

 

I hate command line and almost a noob in Linux myself.

I read manuals and google the rest :-)

 

also LM did not change file system, they add support for new file system.

you do not have to use it though or at least read ahead about the new file system before using it. that what I did when rebuilding my server (not unRaid).

since I am a noob, who comes from windows through and through, it was a quest of epic proportions, so far so good...

 

NO docker without btrfs

so they force us to use it :(

But they did not force you to use a beta version OR to use a swap plugin, that they did not create themselves.

 

I have been using unRAID since 2008 and have never run swap.  I consider myself a proficient power user and have never needed swap.  LimeTech can not curate all plugins, nor would I expect them to.

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If you are not comfortable with using the command line then do not participate in the beta testing at this stage or at least wait until others have automated it.

 

your already trying to do stuff specifically outwith the range of the current test set.

 

thats fine in itself but dont complain when complicated things are complicated :)

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hay, hay, hay, who do you call a command line jokey :-)

 

I hate command line and almost a noob in Linux myself.

I read manuals and google the rest :-)

 

also LM did not change file system, they add support for new file system.

you do not have to use it though or at least read ahead about the new file system before using it. that what I did when rebuilding my server (not unRaid).

since I am a noob, who comes from windows through and through, it was a quest of epic proportions, so far so good...

 

NO docker without btrfs

so they force us to use it :(

 

SA,

 

There are very good reasons for why Docker requires Btrfs in our implementation.  I suggest that you read through the Docker Quick Start Guide for more information.  This is very clearly spelled out.

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hay, hay, hay, who do you call a command line jokey :-)

 

I hate command line and almost a noob in Linux myself.

I read manuals and google the rest :-)

 

also LM did not change file system, they add support for new file system.

you do not have to use it though or at least read ahead about the new file system before using it. that what I did when rebuilding my server (not unRaid).

since I am a noob, who comes from windows through and through, it was a quest of epic proportions, so far so good...

 

NO docker without btrfs

so they force us to use it :(

 

SA,

 

There are very good reasons for why Docker requires Btrfs in our implementation.  I suggest that you read through the Docker Quick Start Guide for more information.  This is very clearly spelled out.

 

Also, if you are going to play with a brand new feature that can have unexpected consequences, maybe don't start it late on a weeknight when you don't have time to back out before you need to get some beauty sleep. :)

 

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To maybe make this easier on folks in the future, here is exactly how I did this...

 

I used Midnight Commander (type mc in putty) to move the whole cache directory to my disk10, and it took about an hour to move about 140GB.  When finished it complained that it could not delete the cache directory, which didn't surprise me.  I left Midnight Commander running/open in my Putty session. Then, I followed the steps in post 1 to

 

[*]stop the array

[*]change the format type of the cache drive

[*]restart the array

[*]format the drive

 

Then I just went back to Midnight Commander and clicked on the cache directory on disk10 (on the right) and hit move again, which then moved everything back to the cache directory.  This took much less time, maybe 20 minutes (I'm not sure why).

 

Then I checked that everything was back on the cache drive, then went to the GUI and installed docker.

 

I couldn't see my cache only shares in the GUI until I rebooted unRAID again, but after that, all seems well.

 

*I just realized that I needed to change my cache only shares back to cache only, this process has set them all to "no"

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Then I just went back to Midnight Commander and clicked on the cache directory on disk10 (on the right) and hit move again, which then moved everything back to the cache directory.  This took much less time, maybe 20 minutes (I'm not sure why).

Remember writing to the array is much slower than writing to a cache drive so you would see significantly faster writes to your now btrfs cache drive. 
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Anyone knows how to fix these uncorrectable errors ?

 

root@tower:/mnt# btrfs scrub status /mnt/tmp/
scrub status for 9e90cef6-5890-4b19-b3af-cee001773b46
        scrub started at Fri Jun 20 21:20:03 2014, running for 1021 seconds
        total bytes scrubbed: 219.88GiB with 2 errors
        error details: csum=2
        corrected errors: 0, uncorrectable errors: 2, unverified errors: 0

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I currently use a SSD for my cache drive..  would changing it to btrfs allow it to have trim support?

Also, TOM any chance of getting this support backported to 5.x ?

btrfs has trim support.  can't speak to backporting of features yet.

 

Sent from my Nexus 5 using Tapatalk

 

 

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