Storage Setup for KVM

EddieJennings

With my redo of my lab server, I'm thinking through how I want to handle storage.

Fedora will be presented a 4 TB block device (Four 2 TB drives in RAID 10). If I recall correctly from doing installs in the past, the installer will want to make three partitions: boot, swap, and a third partition which will be used by LVM to make a volume for / and /home.

For folks who are knowledgeable with KVM, do you keep your images and ISOs in the default location of /var/lib/libvirt/images/? If so, do you usually make a separate volume for /var or just make the volume for / one large volume?

travisdh1

@eddiejennings I don't normally make separate volumes except for /. Everything else normally gets one other volume.

EddieJennings

@travisdh1 said in Storage Setup for KVM:

@eddiejennings I don't normally make separate volumes except for /. Everything else normally gets one other volume.

I think I'm misunderstanding "everything else normally gets one other volume." For the above scenario you'd do something like this?

/boot - a few hundred MB
/swap- whatever is appropriate for 32 GB of RAM
/ - a small number of GB
/var -a large number of GB

stacksofplates

So because of where I work we have to separate volumes. We have separate volumes for /, /var, /var/log, /var/log/audit, /tmp, and /home. If it's a workstation I just use my home directory somewhere for images. If it's a server, I usually just make a large volume for /var.

black3dynamite

On my 500GB laptop, my partition is /boot, / and /swap and I keep the default location for the VMs.

Obsolesce

@eddiejennings set it up how you want. It really doesn't matter unless you have policies like @stacksofplates

travisdh1

@eddiejennings said in Storage Setup for KVM:

@travisdh1 said in Storage Setup for KVM:

@eddiejennings I don't normally make separate volumes except for /. Everything else normally gets one other volume.

I think I'm misunderstanding "everything else normally gets one other volume." For the above scenario you'd do something like this?

/boot - a few hundred MB
/swap- whatever is appropriate for 32 GB of RAM
/ - a small number of GB
/var -a large number of GB

It all depends on the purpose. /boot I did forget about.

A KVM server I'd want to put /var/lib/libvirt/images on it's own volume. If you have a lot of .iso files, possibly those as well. That /var/lib/libvirt/images was the default location for both Fedora27 and Ubuntu Server 17.10.

If you're going to put /var on it's own volume, make sure to do that at install time. You can do it later, but it's more of a pain.

JaredBusch

I do not ususally have my boot volume on the RAID array so I always have a separate mount.

I usually mount the RAID array on /kvm_store_a or some such. I should just mount it to /var/lib/libvirt/images

On my future installs, I likely will, and then link /kvm_store_a to it. Just because I like the quick access path to the location.

Emad R

@eddiejennings

keep your images and ISOs in the default location of /var/lib/libvirt/images/?

Yes I do, but I create 2 new folders there, iso and vm.

Fedora will be presented a 4 TB block device ?
Why dont you separe that a little, and have more fun. Block device I assume DAS, if no why dont you make the storage reliable and robust, and make it its own server, like another fedora or centos install, with RAID 10 and the simplest option to share is NFS, and this way you can have many KVMs and the migration feature will actually work, and you can do RAID on just /var, and you scan scale easily with KVM nodes + KVM nodes can be state file, think salt stack, and you can treat them as pure compute nodes.

travisdh1

@emad-r said in Storage Setup for KVM:

@eddiejennings

keep your images and ISOs in the default location of /var/lib/libvirt/images/?

Yes I do, but I create 2 new folders there, iso and vm.

Fedora will be presented a 4 TB block device ?
Why dont you separe that a little, and have more fun. Block device I assume DAS, if no why dont you make the storage reliable and robust, and make it its own server, like another fedora or centos install, with RAID 10 and the simplest option to share is NFS, and this way you can have many KVMs and the migration feature will actually work, and you can do RAID on just /var, and you scan scale easily with KVM nodes + KVM nodes can be state file, think salt stack, and you can treat them as pure compute nodes.

Because @EddieJennings is talking about his home lab, which will consist of a single 1U server. That hadn't been mentioned in this thread.

EddieJennings

@travisdh1 said in Storage Setup for KVM:

@emad-r said in Storage Setup for KVM:

@eddiejennings

keep your images and ISOs in the default location of /var/lib/libvirt/images/?

Yes I do, but I create 2 new folders there, iso and vm.

Fedora will be presented a 4 TB block device ?
Why dont you separe that a little, and have more fun. Block device I assume DAS, if no why dont you make the storage reliable and robust, and make it its own server, like another fedora or centos install, with RAID 10 and the simplest option to share is NFS, and this way you can have many KVMs and the migration feature will actually work, and you can do RAID on just /var, and you scan scale easily with KVM nodes + KVM nodes can be state file, think salt stack, and you can treat them as pure compute nodes.

Because @EddieJennings is talking about his home lab, which will consist of a single 1U server. That hadn't been mentioned in this thread.

Bah! Folks should be able to read my mind ;). There were some good ideas in this thread though.

What I decided on was giving enough space to / live comfortably, and gave everything else to /var.