Backup Drive accessible from LXC and VM for RSYNC offsite

[New User]

First of all - great software. I'm getting into IT and learning Proxmox.

I want to set-up a remote server running Proxmox and VM for CentoOS7 that will run a webserver. The server specs are Dual - Xeon E5, primary drive - 960GB SSD, 2nd drive - 2TB SATA, 96GB RAM. I want to install Proxmox on SSD drive and mount SATA as a backup. I'm thinking to have proxmox backup CentOS VM to SATA once a week. Then I'm thinking to have rsync from within CentOS7 to SATA drive every 15 mins. And then rsync to offsite backup server nightly. This way if primary SSD drive fails, I can replace it, load Proxmox, restore VM and rsync from SATA (CentOS web server files) files back to a newly created CentOS and hopefully will be out 15 mins of data.

My questions are:
1. In the Proxmox gui when adding storage, what type should I use for SATA mounted drive (Directory, LVM, LVM-thin, ZFS), so that I can perform backup of VM from Proxmox, rsync from CentOS7 VM and rsync to a remote server? I read that LVM doesn't work with rsync.

2. Should I use LXC or VM for CentOS7 (web server)? I understand that VM is based on KVM. I never worked with LXC and not sure the downsides.

3. How to add SATA drive to VM to do rsync every 15 minutes? Is it possible?

Any input is appreciated.
Thanks

 

[dcsapak]

1. In the Proxmox gui when adding storage, what type should I use for SATA mounted drive (Directory, LVM, LVM-thin, ZFS), so that I can perform backup of VM from Proxmox, rsync from CentOS7 VM and rsync to a remote server? I read that LVM doesn't work with rsync.

for rsync and backups you need to choose a file based storage (e.g. directory,nfs)

2. Should I use LXC or VM for CentOS7 (web server)? I understand that VM is based on KVM. I never worked with LXC and not sure the downsides.

either is fine for internal use, lxc is closer to bare metal, but you can only use the host kernel, and it is not as secure as kvm (because of the shared kernel,etc. from the host)

3. How to add SATA drive to VM to do rsync every 15 minutes? Is it possible?

if using lxc, you can bind mount folder to it, in case of a vm you would have to share a folder via nfs/smb/etc. and mount it in the vm

 

[New User]

either is fine for internal use, lxc is closer to bare metal, but you can only use the host kernel, and it is not as secure as kvm (because of the shared kernel,etc. from the host)

With regards to lxc - so I understand that is uses host's kernel. I have a few quick questions:

• Does it mean that I will not be able to move lxc to another Proxmox that runs different kernel version?
• What happens if user initiates kernel update inside lxc (can user even do that)? Will it update host kernel as well? And vice versa, what happens if kernel updated on the host?
• Just from curiosity. You guys are probably running this forum on Proxmox and some linux distro (maybe even CentOS). Are you running it in LXC or VM?

if using lxc, you can bind mount folder to it, in case of a vm you would have to share a folder via nfs/smb/etc. and mount it in the vm

That make sense.

Thanks Dominik!!

 

[dcsapak]

• Does it mean that I will not be able to move lxc to another Proxmox that runs different kernel version?

live migration does not with containers, an offline migration or backup restore works, the container just uses the other kernel then

• What happens if user initiates kernel update inside lxc (can user even do that)? Will it update host kernel as well? And vice versa, what happens if kernel updated on the host?

you could install a package in a container which contains a kernel, but this would do nothing, as containers do not run through a normal boot sequence like bare metal hardware,
a container always uses the kernel of the host (and if the host gets a new kernel, you have to reboot it anyway to use it)

 

[New User]

Wow. Now that makes sense.

Thanks again Dominik!!!