@martin @daftaupe
Tried btrfs à long time ago. Snapshots Can be great for OS Drive. But for data storage nothing Can Beat mdadm+lvm2. Big problem with btrfs : you can't know how much space is still available. (At the Time i checked it at least.)

@hoper @martin You can use btrfs filesystem df for example to know how much space is available (or used). or btrfs filesystem du to get details about a particular file.

@daftaupe @martin
Seems that things change, but according to the FAQ, there are still some issues with this matter (know how much Space left and use it)
btrfs.wiki.kernel.org/index.ph
Il still think that mixing réplication (raid) and file system is a very bad idea.

@hoper @martin Well I'm using it and liking it. I never liked lvm2 and mdadm. That's the beauty of having different alternatives.

@daftaupe @martin
With how many disk ? Did you already Lost a drive or two ? WhatsApp happens then ?
Already loose 2 drives on a raid5 with mdadm and manage to get back all data. (One drive was really out of order, the other one was just suddenly disconected)

@hoper @martin Good for you but I make backups, so I'm not afraid of losing disks :D which is really easy using btrfs send/receive feature.

@daftaupe
You said you have these magic send/receive #scripts, did you already #share them somewhere? Or could you #blog them maybe? 😬🙊
@hoper

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@martin @hoper There's nothing magical :) it's basically having 2 btrfs partitionned drives, making a snapshot of a subvolume and sending that read-only snapshot from one to the other disk. That prevent us from the use a of a tool like rsync as there's an option to send only the increment when you already have subvolumes on the other drive. Based on : btrfs.wiki.kernel.org/index.ph

@daftaupe @martin
So... Just to be sure... Sending data to another drive on the same server is what you call a "backup" ? In this case, it's not only about tools that we disagree :)

@hoper @martin I did mention another disk or drive, it's up to you to think that it's in the same server.

@hoper obviously the (incremental) snapshot should be sent to a backup-machine... 🤓
sending it to another disk in the same server sound like poor-man's raid - and as we know, #btrfs has better raid options 💾

@martin
In m'y mind, a snapshot is not a clone. It's just a sort of "diff" of two devices. Something that you can't separate from it's source.
So I dont understand how you can have a filesystem somewhere, and a snapshot of it elsewhere that can be usefull. A copy, yes. Easy. But a snapshot ? Guess there is plenty of things I dont understand about btrfs.
Maybe the first reason for me to not like it :o)

@daftaupe @martin @hoper

it's not magic it's just

[speaks 14 magical words and all of the shadows in the city disappear]

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