Resize /dev/pve/data and transfer it to /dev/pve/root

[Jonathan Luigi]

Hi Friends,

Ive recently installed proxmox4.4 on a machine that has 2TB of disk space.
The default partition was:
96GB for /dev/mapper/pve-root
8GB for /dev/mapper/pve-swap

and the rest of the disk size was allocated to /dev/pve/data.

What i would want to do is resize/reduce the disk size of /dev/pve/data by 500GB and transfer that space to /dev/pve/root.
Currenty, I already have 2 VMs running on proxmox.

Is there a way to this without a rescue CD? Any form of help would be great.

Thanks!
Jonathan

 

[Mr.Holmes]

Hello Jonathan

Hi Friends,

Ive recently installed proxmox4.4 on a machine that has 2TB of disk space.
The default partition was:
96GB for /dev/mapper/pve-root
8GB for /dev/mapper/pve-swap

and the rest of the disk size was allocated to /dev/pve/data.

What i would want to do is resize/reduce the disk size of /dev/pve/data by 500GB and transfer that space to /dev/pve/root.
Currenty, I already have 2 VMs running on proxmox.

Is there a way to this without a rescue CD? Any form of help would be great.

It depends which filesystem you have at /dev/pve/data resp. /dev/pve/root

* In case of ext(2,3,4):

- shrink the filesystem at /dev/pve/data by resize2fs

- shrink the logical volume by lvreduce - be careful to not make it less than the filesystem has been reduced to, see https://blog.shadypixel.com/how-to-shrink-an-lvm-volume-safely/

- extend the volume /dev/pve/root by lvextend

- extend the filesystem at /dev/pve/root by resize2fs

* in case of xfs:

- xfs filesystem cannot be reduced, therefore copy all current files in /dev/pve/data to a save place

- shrink the logical volume by lvreduce

- create a new filesystem at it and restore the previously saved files

- extend the volume /dev/pve/root by lvextend

- extend the filesystem by xfs_grows (see respective man page)

Success!

Mr.Holmes

 

[Yehudacorsia]

I was writing docs about it, you can read it here

https://docs.google.com/document/d/1_5FFYUGwXQEjNosfBXgn838CdqcUExJrFc5ktqLu52c/edit?usp=drivesdk

 

[liquidox]

I was writing docs about it, you can read it here

https://docs.google.com/document/d/1zKo0qIw4vSq2eSdDuwUvTvoUb0zSaQKO_tB9QxOWypM/edit?usp=drivesdk

Thanks so much for writing this, I needed this today, and your guide saved me a lot of trial and error no doubt !

 

[GoZippy]

I was writing docs about it, you can read it here

https://docs.google.com/document/d/1_5FFYUGwXQEjNosfBXgn838CdqcUExJrFc5ktqLu52c/edit?usp=drivesdk

This came in handy so many times over the years - still works today. Should make this part of official docs for troubleshooting root partition size full... I use ceph and mon and other stuff fills up default small proxmox installer root size while leaving large thin data partition which we rarely use as everything is on ceph pool except a few local vms or containters or backup stuff from time to time... anyhow - well done with easy to follow and understand docs. Thanks!