Changing system HDD -- what files do I have to save?

[whiterabbit]

Hi.
Of course I know that it's possible to upgrade from PVE 2.x --> 3.x --> 4.x.

But as our system with an old proxmox 2.3 installation is quite bloated I wanted to do a fresh installation with the latest version of 4.x on a seperate system HDD. I used a simple PC with no special hardware for the new PVE-installation! This worked and the next step would be to exchange the old system HDD with the new one -- but to leave the existing RAID10-LVM with all the VMs where it is.

I saved some files of the old pve (such as /etc/fstab, /etc/network/interfaces, /etc/udev/rules.d/... ) but I'd like to know if there is something else I have to bear in mind? Or is it enough to compare/exchange these files and come up again with 4.x?
Will it work this way and will I be able to re-import the existing LVM on the RAID-System via Webinterface?
Thanks for a hint ... before I try it

 

[udo]

Hi.
Of course I know that it's possible to upgrade from PVE 2.x --> 3.x --> 4.x.

But as our system with an old proxmox 2.3 installation is quite bloated I wanted to do a fresh installation with the latest version of 4.x on a seperate system HDD. I used a simple PC with no special hardware for the new PVE-installation! This worked and the next step would be to exchange the old system HDD with the new one -- but to leave the existing RAID10-LVM with all the VMs where it is.

I saved some files of the old pve (such as /etc/fstab, /etc/network/interfaces, /etc/udev/rules.d/... ) but I'd like to know if there is something else I have to bear in mind? Or is it enough to compare/exchange these files and come up again with 4.x?
Will it work this way and will I be able to re-import the existing LVM on the RAID-System via Webinterface?
Thanks for a hint ... before I try it

Hi,
"re-import" via Webinterface mean backup on the old VMs and restore on the new one... this is also the official preferred way.

But you can also do an "by hand" update.
1. and most important: have an valid backup of all VMs!
2. after install 4.1 (with updates) on an normal PC - copy following files from the 2.x Server to the new host:
/etc/network/interfaces; an tar-archive from /etc/pve.
3. remove on the new installation the nic-info in /etc/udev/rules.d/70-persistent-net.rules (will be generatet again with the NIC from the right server)
4. shutdown both hosts
5. put the new disk inside the old server and disconnect the old system-disk (important, because lvm with the same name).
6. boot the server and check if the network is ok.
7. restore the tar-file on an temporary place (like /root/old_server/etc/pve ) and put the missing raid-10 entry in /etc/pve/storage.cfg
8. create an VM with an before unused number and look at this config-file (/etc/pve/qemu-server/VMID.conf) - compare this config with the old configs from your tar-file. there are slighty changes... copy the old configs to /etc/pve/qemu-server/ and adapt the settings.
9. boot your VMs...

Udo

 

[whiterabbit]

Thanks for these hints. I just saved /etc/pve and created a new VM on PVE 4.x. When I compare an old .conf with a new one I see these differences:
numa: 0
smbios1: uuid=ae8e2dad-dadf-4077-a696-4acd5a256908

I think these entries didn't exist before? But how/where to find out which parts are necessary there?
"Maybe" the re-import via Webinterface is less complicated...

 

[udo]

Hi,
AFAIK vmdisk and network are a little bit different?!

numa can be set in the gui (and not needet with 1-sockel systems - except with an "big" amd-cpu).
smbios-uuid are also not needed in many VMs (but if you use propritary software which need something like an machid).
You can easily generate an uuid with "uuidgen".

Udo

 

[whiterabbit]

Ok.
Another try....

Old config:
ide0: raid10:500/vm-500-disk-1.raw,size=25G
virtio2: raid10:500/vm-500-disk-2.raw,size=250G
net0: virtio=52:FF:6C:A6:1E:1C,bridge=vmbr1

New config:
ide0: local:800/vm-800-disk-1.qcow2,size=32G
net0: bridge=vmbr0,e1000=35:63:32:37:39:36

You're right! At least the order is not the same. So this is all I have to change?

 

[udo]

right!

 

[whiterabbit]

Ok, thanks.
Now I changed the order "net: bridge <-> MAC" for all .configs in my backup-files. As I can't find any differences in ide/virtio so far I will try it this way.

 

[whiterabbit]

ok, today we changed the system-hdd finally.
if someone else has the same idea: double-check that you don't use "pve" as your name for the lvm-device on your new HDD! otherwise its name will be found twice and a clean boot fails! We had to use vgrename first (Knoppix-Live-CD)