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On Tuesday 22 December 2009 16:21:08 Christian Könitzer wrote: |
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> a question to b): |
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> Can you tell me a fs that supports snappshots (I'm planing to set up a |
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> new server so you can choose a new fs... (now I am using reiserfs)) and |
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> maybe how to use it (link)? So if you say "or LSM" does this mean I can |
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> achieve this also woth LVM? How? |
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> thx... |
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None of the traditional filesystems (ext2|3, reiser) support snapshots. ZFS< |
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Btrfs do, possibly ext4 also (the last is a hunch only). |
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LVM snapshots a volume, not the filesystem on it. So it tracks extents that |
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have changed, not individual files. For backup purposes though, volume and fs |
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snapshots are equivalent. |
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Snapshots with LVM are easy as pie: |
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- create a new volume which is a snapshot of an existing one |
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- mount the snapshot somewhere |
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- copy,backup,etc as you like. The volume is read-only so you can't break it |
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- umount snapshot |
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- destroy snapshot |
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The LVM man pages contain a wealth of data, as does Google and the LVM |
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documentation at redhat.com |
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> |
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> If you have some more tips, my current server runs on a single HDD and a |
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> daily rsync to another computer makes my backup. In my new server I'd |
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> like to improve as much as possible for as less money and energy as |
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> possible (since it's only for me...) so I thought about RAID as well. |
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> Today I'm using very old standard desktop hardware and for the new one I |
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> like to use also standard hardware so I don't know if I can afford a |
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> RAID-5 card or so... and I never made software RAID... do you have some |
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> recommendations (links?)? thx |
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Cheap dumbass hardware raid is not worth the money. This includes every single |
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on-board raid controlled it has ever been my misfortune to behold. Some of |
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them are even called RAID but aren't - they're just a fancy multipath thingy |
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and might let you only choose RAID 1 or 5, or even only RAID 1 in some cases |
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Software raid built into the linux kernel is a far better solution. Again, |
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Google will return enough hits that it will take you a year to read all the |
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good docs.... |
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Proper hardware add-on cards *are* worth the money though and deliver great |
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results. Your post indicates that you won't want to spend what they cost |
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though |
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|
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-- |
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alan dot mckinnon at gmail dot com |
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