free space after installation...where?

[stuartbh]

Forum members,

I installed Proxmox 6.1-1 from the Proxmox installation ISO (choosing an EXT4 filesystem for this initial try, though I prefer to use ZFS eventually) and the installation went perfectly. In succession to having a bootable system I logged into Debian via SSH. From that perspective I was unable to see or notice where all the free space was on the 2TB HD it was installed upon. I saw LVM volumes and such, inclusive of one that was called "pve-data", but seemed entirely unmountable. How do I access via the command line the free space that is available post installation and pre setup of any virtual machines? How would I mount or access the free space after installation in this manner via SSH?

One other question is, how safe or problematic is it to use ZFS if the target HD is an SSD drive? I know there is trim and that, but, what options in ZFS ought be used to assure that the SSD has the longest possible life?


Stuart

 

[aaron]

If you select a file system other than ZFS, Proxmox VE will use LVM. The pve-data volume is the VG in which the guests will allocate their virtual disks. Once you create a guest, the output of lvs or lsblk should show them.

The logical volumes are used as block devices and are passed to the VM which then will partition and format it as it sees fit.

One other question is, how safe or problematic is it to use ZFS if the target HD is an SSD drive?

Not worse than another file system. Proxmox VE will write a bit of logs each day which could cause problems if installed on a very cheap SSD that cannot handle the writes.

 

[stuartbh]

If you select a file system other than ZFS, Proxmox VE will use LVM. The pve-data volume is the VG in which the guests will allocate their virtual disks. Once you create a guest, the output of lvs or lsblk should show them.

The logical volumes are used as block devices and are passed to the VM which then will partition and format it as it sees fit.

Would it then be reasonable to suggest that in succession to installing Proxmox VE and in precedence to creating any guests, if one were to login to the Proxmox VE host (via SSH for example) and create a volume in the pve-data group, it could then be mounted in Debain Linux and used for some activity, then once that activity is completed and the logical volume unmounted and removed, it would then leave Proxmox VE a "post installation like state" and able to function as designed thereafter?

Not worse than another file system. Proxmox VE will write a bit of logs each day which could cause problems if installed on a very cheap SSD that cannot handle the writes.

Are there any recommended configuration parameters for ZFS that would limit its activity in order to cause only the minimum required level of disk activity to occur? It is a "home lab" based server, so auditing logs, and such are of little concern to me.

 

[apoc]

ZFS writes all IO to disk, that's the way it operates. You can tweak a lot of settings for ZFS, but I wouldn't recommend it.
If you use a SLOG (separate log device) for ZIL then you could copy the majority of the data onto the HDD before adding the SLOG to the pool.
Otherwise, get a decent datacenter grade SSD from Ebay. These SSDs become quite cheap in a decent size (480GB -> saw one for 60€ with 90%+ lifetime left).