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Size: 2193
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| Deletions are marked like this. | Additions are marked like this. |
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| Describe KVM Host Disk Layout here. | = KVM Host Disk Layout = |
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| === KVM host === | 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. |
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| ==== Physical Disks ==== | == 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 ==== |
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| sda2 15360M | sda2 15616M |
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| sdb2 15360M | sdb2 15616M |
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| md1_crypt lvm (vg1) | md1_crypt lvm (vg_system) |
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| ==== LVM volumes ==== | ==== 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. |
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| vg1 root 2G (/dev/vg1/root) vg1 swap 512M (/dev/vg1/swap) |
vg_system root 2G (/dev/vg_system/root) vg_system swap 512M (/dev/vg_system/swap) |
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| ==== Filesystems and mountpoints ==== | ==== Filesystems and Mountpoints ==== I use btrfs myself, and has not had any problems with it. btrfs is chosen for its flexibility, but any modern filesystem should be sufficient. |
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| /dev/vg1/root / (btrfs) /dev/md0 /boot (btrfs) /dev/vg1/swap (swap) |
/dev/vg_system/root / (btrfs) /dev/md0 /boot (btrfs) /dev/vg_system/swap (swap) |
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=== KVM Host Disks for Guest Filesystem Images === ==== Physical Disks and Partitions ==== {{{ sdc 6T sdc1 5588G sdd 6T sdd1 5588G }}} ==== Raid ==== {{{ md2 raid1 (sdc1, sdd1) }}} ==== 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 (btrfs) }}} |
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 256M sda2 15616M sdb 16G sdb1 256M sdb2 15616M
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 btrfs myself, and has not had any problems with it. btrfs is chosen for its flexibility, but any modern filesystem should be sufficient.
/dev/vg_system/root / (btrfs) /dev/md0 /boot (btrfs) /dev/vg_system/swap (swap)
KVM Host Disks for Guest Filesystem Images
Physical Disks and Partitions
sdc 6T sdc1 5588G sdd 6T sdd1 5588G
Raid
md2 raid1 (sdc1, sdd1)
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 (btrfs)