[CentOS-virt] lvm and kvm

Mon Aug 15 19:54:51 UTC 2011
James B. Byrne <byrnejb at harte-lyne.ca>

I am performing some configuration testing on a kvm host.  When
installing a guest operating system is it advisable to place each
instance in a separate lv or better to accept the default and store
them on the root file system?

Respecting lvm, does one configure lvs in a virtual server to take
space from the main vg or does one allocate lv space from inside
that allocated to the virtual instance?  Is it even considered
advisable to use lvs with virtual guests?

To give an example, if I were to configure an smtp server on bare
metal I might use the following disk layout:

vg_bare 500Gb

/ lv_root 8Gb
/boot lv_boot 1Gb
/tmp lv_tmp 8Gb
/var/log lv_log 8Gb
/var/spool/mail lv_mail 16Gb

In a kvm setup, if I wish to do this, would I first create an lv
just to host the virtual image and then assign lv s from the space
allocated to that image file?

vg_bare 500Gb

/ lv_root 8Gb
/boot lv_boot 1Gb
/tmp lv_tmp 8Gb
/var/log lv_log 8G

/var/lib/libvirt/images/lv_virt01 32Gb
/var/lib/libvirt/images/lv_virt02 32Gb
.  .  .

and so forth?  Or is it worth the bother to have lv s in a virtual

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