On 09/13/2011 12:38 PM, Indunil Jayasooriya wrote:
On Tue, Sep 13, 2011 at 2:00 PM, Rudi AhlersRudi@softdux.com wrote:
On Tue, Sep 13, 2011 at 1:52 AM, Thomas Dukestdukes@sc.rr.com wrote:
-----Original Message----- From: centos-bounces@centos.org [mailto:centos-bounces@centos.org] On Behalf Of ken Sent: Monday, September 12, 2011 12:36 AM To: CentOS mailing list Subject: Re: [CentOS] Vitualization and Partitioning
On 09/11/2011 11:10 PM Emmanuel Noobadmin wrote:
Hi,
When I do the install, do I or should I setup a separate partition for guest
That would be better from a performance point of view
OS's? From the redhat docs, it looks like the guest OS's reside at /var/lib/libvirt/images/.
This should be using files as disk files, which I did and
found it to
be a problem when there is heavy I/O.
I like LVM (for the reasons you cite). Would you (anyone?) say it's best to have one LV per guest or one LV for all guests?
tnx.
I'm new to this but I would think you would want a separate LV for each guest. Seems I read somewhere, that you need one core per guest as well. That's why I'm opting for the Xeon processor rather than the iCore(x). Four cores v. two. More options.
Can't believe this thread hasn't stirred more response. Maybe we all are in the learning phase.
Eddie
We use LVM on all our virtual hosting servers since it's much easier to manage.
You basically setup a PV volume spanning the whole drive(s), and then a 10GB (or larger if you need to) LVM volume for /root, 10GB for /var, 2GB for /tmp& 5GB for /home.
Then for any VM's just add LVM volumes as needed, for example:
/dev/Volume001/vm1_root - 10GB /dev/Volume001/vm1_swap - 1GB
Another tip: Don't use the default LVM volume naming scheme, but instead name the LVM volumes according to your server name, i.e. server01& server02. This way if server01's HDD crashes and you need to mount it on server002 for recovery purposes, you won't have conflicting LVM volumes
Hi, Interesting subject. Let me participate too. Suppose we are going to install 3 VMs, I think it is proper to create separate LVMs like this
/dev/vg_server1/lv.server1
and mount it as
/var/lib/libvirt/images/server1
/dev/vg_server2/lv.server2
and mount it as
/var/lib/libvirt/images/server2
/dev/vg_server3/lv.server3
and mount it as
/var/lib/libvirt/images/server3
Don't use separate volume groups. Also don't mount the logical volumes but instead use them directly as block devices. That should give you better performance as the i/o path is then VM->block device instead of VM->filesystem->block device.
If I mount in that way, Is it possible to take live snapshot backup while these 2 servers are running?
Remember that you need to allocate enough space for the snapshot volume to contain all the blocks that change on the VM while the backup is running i.e. if your backup is running for an hour and during that hour your VM receives 2G worth of writes/update then you need to have at least a size of 2G for your snapshot volume. This also means that you have to reserve enough space in the volume group to create a big enough snapshot volume.
Also keep in mind that the backup you will get will not be fully consistent only crash consistent.
Regards, Dennis