Hi Proxmoxers 
I've got a production Debian server running a few KVM VM's that I manage manually.
I want to install Proxmox on my server without risking breaking anything, and without causing unexpected, unplanned, excessive downtime.
I have an idea of how to make the transition easily and safely. Please let me know if you see any problems with my idea.
My configuration is as follows
2 Hard drives in a software mirror RAID configuration.
I know Proxmox won't help me manage/monitor my software RAID; that's fine with me.
/dev/sd[ab]1 are mounted as /dev/md0 /boot (GRUB)
/dev/sd[ab]2 are mounted as /dev/md1 LVM PV
I'm currently booting /dev/mapper/myoriginaldebianroot which is an LVM LV.
I've got plenty of free space on my PV, so I'd like to make a new PV, call it proxmoxtest. Then install Debian 8 on it via debootstrap.
Preparation (while still in production)
1. Backup /boot and other essential files/VM's to a physically separate machine in-case of disaster
2. Create new LV for Deb8 Proxmox /dev/mapper/proxmoxtest, format as EXT4 or XFS
3. Install Deb8 with debootstrap on /dev/mapper/proxmoxtest
4. Create new LV for testing KVM's in PVE /dev/mapper/proxmoxvms Then copy my production VM's into it for testing. [Optional?]
During short scheduled downtime (a few hours)
1. Change GRUB to tell the kernel (3.16) to boot from /dev/mapper/proxmoxtest.
2. Boot new Deb8 and run apt-get update && apt-get upgrade && apt-get dist-upgrade.
3. Install Proxmox.
4. Add /dev/mapper/proxmoxvms as a storage pool.
5. Try get production VM's running.
If all goes amazingly well, I can get it all done in a single session.
If I have problems and I can't get it running in one session, I want to change my grub to boot from /dev/mapper/myoriginaldebianroot again. (I will restore my backup of /boot (including the kernel and grub cfg etc as necessary)
Big important questions
Will proxmox corrupt/damage my software raid?
Will proxmox delete or destroy my LVM PV or any of my LVM LV's?
Will proxmox modify or interfere with /dev/mapper/myoriginaldebianroot in any way?
Are there any risks I've not considered?
Do you have any suggestions for completing the transition smoothly?
* Note
I'm aware that PVE will install it's own kernel. If I complete the change over multiple sessions, I'll have two backups for /boot. One for my original system, and one for PVE.
I've got a production Debian server running a few KVM VM's that I manage manually.
I want to install Proxmox on my server without risking breaking anything, and without causing unexpected, unplanned, excessive downtime.
I have an idea of how to make the transition easily and safely. Please let me know if you see any problems with my idea.
My configuration is as follows
2 Hard drives in a software mirror RAID configuration.
I know Proxmox won't help me manage/monitor my software RAID; that's fine with me.
/dev/sd[ab]1 are mounted as /dev/md0 /boot (GRUB)
/dev/sd[ab]2 are mounted as /dev/md1 LVM PV
I'm currently booting /dev/mapper/myoriginaldebianroot which is an LVM LV.
I've got plenty of free space on my PV, so I'd like to make a new PV, call it proxmoxtest. Then install Debian 8 on it via debootstrap.
Preparation (while still in production)
1. Backup /boot and other essential files/VM's to a physically separate machine in-case of disaster
2. Create new LV for Deb8 Proxmox /dev/mapper/proxmoxtest, format as EXT4 or XFS
3. Install Deb8 with debootstrap on /dev/mapper/proxmoxtest
4. Create new LV for testing KVM's in PVE /dev/mapper/proxmoxvms Then copy my production VM's into it for testing. [Optional?]
During short scheduled downtime (a few hours)
1. Change GRUB to tell the kernel (3.16) to boot from /dev/mapper/proxmoxtest.
2. Boot new Deb8 and run apt-get update && apt-get upgrade && apt-get dist-upgrade.
3. Install Proxmox.
4. Add /dev/mapper/proxmoxvms as a storage pool.
5. Try get production VM's running.
If all goes amazingly well, I can get it all done in a single session.
If I have problems and I can't get it running in one session, I want to change my grub to boot from /dev/mapper/myoriginaldebianroot again. (I will restore my backup of /boot (including the kernel and grub cfg etc as necessary)
Big important questions
Will proxmox corrupt/damage my software raid?
Will proxmox delete or destroy my LVM PV or any of my LVM LV's?
Will proxmox modify or interfere with /dev/mapper/myoriginaldebianroot in any way?
Are there any risks I've not considered?
Do you have any suggestions for completing the transition smoothly?
* Note
I'm aware that PVE will install it's own kernel. If I complete the change over multiple sessions, I'll have two backups for /boot. One for my original system, and one for PVE.