[mdlug] Virtual Server Time

[Dan Pritts]

>> 
>> 	LVM on the Virtual Machines or on the drives that will hold the VMs
>> or the drives that will hold the data? I have been using a very effective
>> for me drive layout for a little over 10 years now, it's evolved slightly,
>> but I have never run into any issues with it. There are probably a few
>> ways to do some elements better though.
> 
> I recommend it for both hosts and guests.  LVM provides options
> like resizing partitions and hot migration of a failing disk.
> All you need to do is extend a / partition live on a produciton
> server one time, and you'll be sold!

LVM is great, but I dont’ see the point of using it inside VMs.  

my typical practice is to create a single virtual disk in the hypervisor for
each filesystem.  Another for swap, if you configure swap - I generally do, 
but in some cases it is counter-productive.  

anyway, at least with vmware, it is trivial to resize the virtual disks from
the hypervisor.  Tell the host to rescan the device, and resize the filesystem.

One thought on this - it’s an open question whether you want to put a partition
table on these virtual disks.  I started out doing it that way, just on the theory of
the principle of least surprise.

But...it’s a pain in the ass to have to repartition when you resize the disk.  And, it could be
a destructive operation if you screw it up.  Of course, I take a snapshot first.

for the OP - snapshots are arguably the most powerful capability of running under
a hypervisor.

danno