Storage "local" and "local-zfs"

[metainformatica]

Hi all!!

I installed proxmox 4.4 on HP DL380 G7 server 2x cpu X5670, 72 GB ram, p410 controller, 2 hdd Wd red 1TB.
Before installation I create single disk RAID-0 volumes, not JBOD because p410 controller not support it.
During installation process I chose "zfs (RAID0)" in "target disk options",.

After installation I see 2 storage: "local" and "local-zfs" (see image below), can you help me to understand?

maybe a problem with single disk RAID-0 configuration?
Is better to use a dedicated HBA/JBOD controller?

Thanks
Marco

 

[dietmar]

After installation I see 2 storage: "local" and "local-zfs" (see image below), can you help me to understand?

This is expected behavior (what is the problem?).

Besides, using RAID0 for zfs is not recommended, so I would suggest to use simple BOD controller.

 

[metainformatica]

First of all many thanks for your answer!

I would understand why I see 2 local storage on the same level... which one I have to use?

I never used ZFS and I would like to learn the basics.. where can I find information or manual?
can you suggest me?

there will be training courses in Italy in the near future??

thank you again

Marco

 

[dietmar]

local: file-level storage - you can upload iso images and place backups there.

local-zfs: this is used to store VM images.

Note: Both resides on the same zfs pool.

 

[metainformatica]

in local storage I see usage 4,84GB of 877GB..
in local-zfs storage I see 12,68GB of 885GB..
as if they where 2 separated hard drives!!

 

[LnxBil]

Please post the output of

zfs list

and we'll explain what you see. For further ZFS information, the manpage is really, really good. Manpage of zpool and zfs.

 

[metainformatica]

thank you again

 

[LnxBil]

I'd say that different values are from the compression and the fill grade of your system.

 

[vkhera]

As your screenshots show, the "local" is a directory. It just happens to live on a ZFS file system.

Your "local-zfs" is a ZFS storage, which means that when you create a disk, it will create a ZFS volume to store the raw data. This is the most efficient storage you can have for this purpose, and you can use ZFS feature individually on each such volume (such as setting compression, snapshots and zfs send/receive to copy them, etc.) You see your vm-100 disk is built this way.

Because it is a separate ZFS object, its storage is reported differently from the zfs file system.

 

[metainformatica]

thank you vkhera

 

[Uni211]

How can I find the image that is on local-zfs?
I want to replace it for the new image.

 

[Uni211]

No one knows?

 

[eiger3970]

Without zfs, the VM.iso image is in /var/lib/vz/template/iso.
With zfs, I can't find VM.iso myself?

 

[ckhung]

The iso images are in /var/lib/vz/template/iso/

As for the installed system, it lives in a block device, not in a qemu image file (If you chose local-zfs when installing the vm),
For example, in my system "zfs list" shows "rpool/data/vm-207-disk-1" among other things.
So the device file for my vm#207 is /dev/zvol/rpool/data/vm-207-disk-1
and I can mount it to look into it.

I am not a zfs expert but this picture from my blog may help you get started.
If you wan to learn systematically, Aaron Toponce has a series of articles about zfs on linux.
(Sorry I am not allowed to post links yet.)

 

[wellbein]

Many thanks Ckhung !
it's the graphic representation i was looking for several days.
because of my lack of linux knowledge, I couldn't 'materialize' this famous ZFS.
much clearer now, many thanks.

 

[LnxBil]

View attachment 6735

Very nice picture and good work ... sorry... but ... there is the physical volume layer in the traditional and the vdev layer in the zfs side missing. Besides that very good and only minor or internal things.