Differences between revisions 1 and 12 (spanning 11 versions)

BTRFS filesystem

Create a raid1 mirror disk setup raid1 for both data and metadata
- mkfs.btrfs -m raid1 -d raid1 /dev/sdb /dev/sdc /dev/sdd /dev/sde
- Now find uuid with sudo blkid /dev/sd*
  - Add more hd's
    - ```
           btrfs device scan
           btrfs device add /dev/sdc2 /
           btrfs filesystem balance /
           btrfs balance start -dconvert=raid1 -mconvert=raid1 /
```
reflinks
- cp --reflink name1 name4
- reflinks are supported by BTRFS and OCFS2 and support transparent copy on write which is especially useful for snapshotting.
- Note that since separate inodes are used, one can have different permissions to access the same data.
- Reflinks have the same use as hardlinks, but are more space efficient and generally handle all subsequent operations on a file, not just unlink().
If you have virtual images on a btrfs, cow(copy on write) will cause a lot of fragmentation, turn it of for the directory of file with
- this disables cow(fragmentation) and also crc calculations on the files.
  - ```
       chatter +C /path
```

defrag with

   btrfs filesystem defragment /path/file

or faster for large files

     cp --reflink=never vbox.vdi vbox.new.vdi ; rm vbox.vdi ;

Create raid array, raid1 all data mirrored once.
- # mkfs.btrfs -m raid1 -d raid1 -L root /dev/disk/by-label/root1 /dev/disk/by-label/root2 /dev/disk/by-lab

el/root3 /dev/disk/by-label/root4

Mount options, add compress
subvolumes
- mount option subvol=homevol

Install on multi disk

Will install on multiple disks
- ```
   sudo dpkg-reconfigure grub-pc 
```
Use uuid , same for all disks.
- ```
   sudo blkid /dev/sd* 
```

BTRFS maintenace

SCRUB disks in background, recovering for good copy in raid1 config

   sudo btrfs filesystem show
   sudo btrfs filesystem df /
   sudo btrfs scrub start /
   sudo btrfs scrub status -d /

HP Server Raid tools

http://dmatwork.blogspot.com/2010/07/installation-of-hp-array-configuration.html

...

-  ⇤ ← Revision 1 as of 2011-11-01 11:59:16 → 
  Size: 413
  Editor: PieterSmit
  Comment:
+   ← Revision 12 as of 2015-11-09 05:49:09 → ⇥
  Size: 2261
  Editor: PieterSmit
  Comment:
-Deletions are marked like this.
+Additions are marked like this.
 Line 6:
+ * Create a raid1 mirror disk setup raid1 for both data and metadata
   {{{ mkfs.btrfs -m raid1 -d raid1 /dev/sdb /dev/sdc /dev/sdd /dev/sde }}}
   * Now find uuid with {{{ sudo blkid /dev/sd* }}} 
     * Add more hd's
       {{{
       btrfs device scan
       btrfs device add /dev/sdc2 /
       btrfs filesystem balance /
       btrfs balance start -dconvert=raid1 -mconvert=raid1 /
-Line 7:
+Line 16:
+       }}}
 * reflinks
   {{{ cp --reflink name1 name4 }}}
   * reflinks are supported by BTRFS and OCFS2 and support transparent copy on write which is especially useful for snapshotting. 
   * Note that since separate inodes are used, one can have different permissions to access the same data. 
   * Reflinks have the same use as hardlinks, but are more space efficient and generally handle all subsequent operations on a file, not just unlink().
 * If you have virtual images on a btrfs, cow(copy on write) will cause a lot of fragmentation, turn it of for the directory of file with
   * this disables cow(fragmentation) and also crc calculations on the files.
     {{{
     chatter +C /path
     }}}
    
 * defrag with
   * {{{
   btrfs filesystem defragment /path/file
   }}}
   * or faster for large files
     {{{
     cp --reflink=never vbox.vdi vbox.new.vdi ; rm vbox.vdi ;      }}}
-Line 14:
+Line 42:
-   * mount optione subvol=homevol
+   * mount option subvol=homevol


== Install on multi disk ==
 * Will install on multiple disks
   {{{ 
   sudo dpkg-reconfigure grub-pc }}}
 * Use uuid , same for all disks. 
   {{{
   sudo blkid /dev/sd* }}}

== BTRFS maintenace ==
 * SCRUB disks in background, recovering for good copy in raid1 config
   {{{
   sudo btrfs filesystem show
   sudo btrfs filesystem df /
   sudo btrfs scrub start /
   sudo btrfs scrub status -d /
   }}}
== HP Server Raid tools ==
 * http://dmatwork.blogspot.com/2010/07/installation-of-hp-array-configuration.html