Differences between revisions 24 and 31 (spanning 7 versions)
⇤ ← Revision 24 as of 2021-01-22 13:12:54 →
Size: 2047
Editor: Kristian Kallenberg
Comment:
← Revision 31 as of 2021-02-26 19:33:43 → ⇥
Size: 2212
Editor: Kristian Kallenberg
Comment:
Deletions are marked like this. Additions are marked like this.
Line 16: Line 16:
sda1 256M
sda2 15616M		 sda1 512M
sda2 15360M
Line 20: Line 20:
sdb1 256M
sdb2 15616M		 sdb1 512M
sdb2 15360M
Line 52: Line 52:
I use ext4 myself, and have chosen this for its stability, but any modern filesystem should be sufficient.
Line 53: Line 55:
/dev/vg_system/root / (btrfs)
/dev/md0 /boot (btrfs)		 /dev/vg_system/root / (ext4)
/dev/md0 /boot (ext4)
Line 63: Line 65:
sdc 2T
sdc1 1856G		 sdc 6T
sdc1 5588G
Line 66: Line 68:
sdd 2T
sdd1 1856G		 sdd 6T
sdd1 5588G

sde 6T
sde1 5588G

sdf 6T
sdf1 5588G
Line 73: Line 81:
md2 raid1 (sdc1, sdd1) md2 raid5 (sdc1, sdd1, sde1)
Line 98: Line 106:
/dev/vg_storage/media /mnt/media (btrfs) /dev/vg_storage/media /mnt/media (ext4)

KVM Host Disk Layout

This disk layout has several layers. It uses btrfs, on top of LVM, on top of luks encryption, on top of raid, on top of the disk partitions.

Hardware

Two 16G SSD disks are used for the KVM Host. Two 2T SATA disks are used for the KVM Guests filesystem images.

Mark your disks! Spend time finding your disks S/N. Put a physical sticker on the disk. In the future this will help you identify a failing disk.

KVM Host Disks

Physical Disks and Partitions

sda     16G
sda1   512M
sda2 15360M

sdb     16G
sdb1   512M
sdb2 15360M

Raid

md0 raid1 (sda1, sdb1)
md1 raid1 (sda2, sdb2)

Luks

md1 luks (md1_crypt)

LVM

md1_crypt lvm (vg_system)

LVM Volumes

Initially the swap partition was 512M, but it ran full and was increased to 1G. That ran full as well, so a swap partition on the second volume was added too. It seems the KVM host happily swaps and will use many gigabytes of swap if the swap partition is there. The consequence is that the guests are slower to respond. So I recommend only swapping if you are really running out of memory. 

vg_system root 2G   (/dev/vg_system/root)
vg_system swap 512M (/dev/vg_system/swap)

Filesystems and Mountpoints

I use ext4 myself, and have chosen this for its stability, but any modern filesystem should be sufficient. 

/dev/vg_system/root /     (ext4)
/dev/md0            /boot (ext4)
/dev/vg_system/swap       (swap)

KVM Host Disks for Guest Filesystem Images

Physical Disks and Partitions

sdc     6T
sdc1 5588G

sdd     6T
sdd1 5588G

sde     6T
sde1 5588G

sdf     6T
sdf1 5588G

Raid

md2 raid5 (sdc1, sdd1, sde1)

Luks

md2 luks (md2_crypt)

LVM

md2_crypt lvm (vg_storage)

LVM Volumes

vg_storage media 4G (/dev/vg_storage/media)
vg_storage swap  4G (/dev/vg_storage/swap)

Filesystems and Mountpoints

/dev/vg_storage/swap             (swap)
/dev/vg_storage/media /mnt/media (ext4)

None: KVM Host Disk Layout (last edited 2024-01-29 20:16:56 by Kristian Kallenberg)