Question about ZFS raid-1

[Maddrag]

Hello,
Please, explain someone, why, after installing Proxmox on zfs raid-1, do I have a total storage capacity equal to the sum of two disks?
For example: in a test environment I installed Proxmox on a zfs raid-1 of 2 disks of 100 GB each. After installation, I have 2 storages: local and local-zfs, each of which has 100 GB of space, which are filled independently of each other. Where did the local storage space come from? And does this mean that I can record almost 200 GB of information that will be completely duplicated?

 

[Dunuin]

You don't have. Both storages share the same 100G (thin provisioning). So both will tell you 100G + 100G while empty but you can't add them up. Put 50GB of files on "local" and it will tell you that "local" got 50GB of 100GB used. "local-lvm" will then tell you that 0 of 50GB are used. In other words: Both storages will then tell you that 50GB are available.

 

[ce3rd]

Hi, for my understanding, this is because both are in the same zfs-pool -> rpool (which is 100GB) - (one is type dir and one is type ZFS):

https://pve.proxmox.com/wiki/ZFS_on_Linux

"The installer automatically partitions the disks, creates a ZFS poolcalled rpool, and installs the root file system on the ZFS subvolumerpool/ROOT/pve-1.

Another subvolume called rpool/data is created to store VMimages. In order to use that with the Proxmox VE tools, the installercreates the following configuration entry in /etc/pve/storage.cfg"

 

[Maddrag]

Thanks for answers. Now it became clear.