Confused New User of Proxmox adding second Hard drive


New Member
Mar 13, 2019
First of all: I like Proxmox.
But I am stuck at the moment. My Experience with Linux is... bit basic. The search was also not giving much of an explanation...

My Config and what I want to do:

I am using a Computer with SSD 250GB (sdb) setup with Proxmox as Host. Hosts Name is prox
I recently added a second SATA HDD 1.8T (sda) for Containers and to provide Storage to Containers.
these Information I was following to create a volume etc...
until here: (switched sdb with sda)
"Create a volume group named “vmdata” on /dev/sda1
# vgcreate vmdata /dev/sda1"
"A real world example:
# lvcreate -n vz -V 1.8T pve/data" (worked fine)

Stuck I am here:

Now a filesystem must be created on the LV.
# mkfs.ext4 /dev/pve/vz
At last this has to be mounted.
be sure that /var/lib/vz is empty. On a default installation it’s not. <<<

My question: Can I just move from /var/lib/vz to a different Directory?
# mkfs.ext4 /dev/pve/vz1 <<< this?
Do I need to change the previous as well? >> # lvcreate -n vz -V 1.8T pve/data" (worked fine)

How e.g. what do I need to change in order to do so?
I believe I need a LVM-Thin to use the HDD as additional Storage?

On the GUI I see now: Disks > LVM > pve (dev/sdb3 223.07GB)
and: Disks > LVM > vmdata (/dev/sda1 0% 1.82TiB)
Last edited:
be sure that /var/lib/vz is empty. On a default installation it’s not. <<<

Hey there, it's fine to mount over /var/lib/vz, just make sure the entry exists in fstab so it can be properly mounted on boot. The exists date will still be there, however, all new date will written to 2nd disks.

NOTE: Make sure to create the directory structure on the new disk, if PVE doesn't create them automatically.

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Thanks. Let me get this right:
You say I can just follow the way further, but my complete storage will move from sdb3 to sda1?
But then I will loose free space... the 140GIB from the SSD, right?
If it's done correctly, yes, that is you can verify with 'mount | grep /var/lib/vz'. The logical volume will be mounted over/on top of /var/lib/vz.

But then I will loose free space... the 140GIB from the SSD, right?

Technically, yes. how much space are you using in /var/lib/vz currently? You can however move over the data to the new disk than mount the new disk at /var/lib/vz.

See post below.
Last edited:
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Reactions: Kruuhndan
Ok thank you for that information.

Tried it via GUI in: Datacenter > Storage > add > LVM-Thin>
> ID set to "local-lvm1"
> Volume Group (I choose the new one) "vmdata"
> ThinPool: 'here I cannot choose anything' The dropdownmenu just disappears upon opening.
> Content: DiskImage, Container

So far, so good, but what do I do with that Drop-down-menu? Think I need to finish on the CLI for now.
I am trying that now, will come back upon questions.
Here the Information you requested:
Output of vgs:
 VG     #PV #LV #SN Attr   VSize   VFree
  pve      1   7   0 wz--n- 223.07g 16.00g
  vmdata   1   0   0 wz--n-   1.82t  1.82t

Output of lvs:
  LV                      VG  Attr       LSize   Pool Origin        Data%  Meta%  Move Log Cpy%Sync Convert
  data                    pve twi-aotz-- 140.45g                    3.96   0.24
  root                    pve -wi-ao----  55.75g                               
  snap_vm-100-disk-0_Save pve Vri---tz-k  32.00g data vm-100-disk-0             
  swap                    pve -wi-ao----   8.00g                               
  vm-100-disk-0           pve Vwi-aotz--  32.00g data               14.65       
  vm-100-state-Save       pve Vwi-a-tz--   2.49g data               33.22       
  vz                      pve Vwi-a-tz--   1.80t data               0.00

Output of pvs:
  PV         VG     Fmt  Attr PSize   PFree
  /dev/sda1  vmdata lvm2 a--    1.82t  1.82t
  /dev/sdb3  pve    lvm2 a--  223.07g 16.00g


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