[clug] Seeking FOSS Hypervisor and Management GUI
George at Clug
Clug at goproject.info
Wed Oct 1 17:25:44 MDT 2014
So far I have always created VMs and servers with all files in
the one partition. I have not understood any usefulness for having
separate partitions. My main concern is that I do not know how large
to make the partitions and fear they will fill up as updates are
installed. Some operating systems are like that. I have one
application that wants to install itself to /usr/share and thus takes
up space I would not have necessarily provided for. From my limited
understanding, it is /var/log and in particularly /home that are known
to grow large, where as I would expect the other directories (what
should I call them?) like /etc /bin /sbin, etc will only increase
slightly, if at all. I guess partitioning would be a topic of its own.
$ virsh snapshot-list
http://wiki.libvirt.org/page/VM_lifecycle
As for FOSS Hypervisor and Management GUI, my efforts for installing
Virt-Manager 1.1 seemed to have not completely succeeded. When
attempting to use my installation of Virt-Manager 1.1 I found that
there was no Connect/Disconnect for the CDROM, thus I could not add or
remove CD/DVDs or ISOs of CD/DVDs. In the end I uninstalled and
reinstall Virt-Manager 0.10 which then left me with no GUI for
managing snapshots.
I have yet to try restoring from snapshots or consolidating snapshots,
however I have now used the command line to take snapshots (took a
while for the first snapshot to be taken). I tried to take a
snapshot of a powered down raw image but of course it would not do
this, the image has to be Qcow2. I also took a live snapshot and a
snapshot of the VM when it was shutdown.
It would be nice if I could give snapshots meaningful names and/or a
description as the number for the snapshot has little meaning unless
you record this somewhere. Various doco suggests "virsh
snapshot-create-as myvm snapshot1 "snapshot1 description" --disk-only
--atomic", but then says "The commands are not fully implemented in
libvirt yet" ?
See commands below;
http://virt-tools.org/learning/start-list-with-command-line/
[ovnode01]$ virsh -r -c qemu:///system list --all
Id Name
State
----------------------------------------------------
15 mc54
running
- MC43
shut off
- mc44
shut off
- Minecraft1 shut
off
- Minecraft2 shut
off
- Win8Ent01 shut
off
[root at ovnode01 RPMS]# virsh list --all
Id Name
State
----------------------------------------------------
12 mc54
running
- MC43
shut off
- mc44
shut off
- Minecraft1 shut
off
- Minecraft2 shut
off
- Win8Ent01 shut
off
[root at ovnode01 RPMS]# virsh snapshot-list mc54
Name Creation
Time State
------------------------------------------------------------
[root at ovnode01 RPMS]# virsh snapshot-create mc54
Domain snapshot 1412165432 created
[root at ovnode01 RPMS]# find / -name mc54
/var/lib/libvirt/qemu/snapshot/mc54
[root at ovnode01 RPMS]# find / -name mc54*.*
/etc/libvirt/qemu/mc54.xml
/var/lib/libvirt/images/mc54.img
/var/lib/libvirt/qemu/mc54.monitor
/var/log/libvirt/qemu/mc54.log
[root at ovnode01 RPMS]# ls -al /var/lib/libvirt/qemu/snapshot/
total 4
drwxr-xr-x. 3 qemu qemu 25 Oct 1 22:12 .
drwxr-x---. 6 qemu qemu 4096 Oct 1 22:01 ..
drwxr-xr-x. 2 root root 35 Oct 1 22:12 mc54
[root at ovnode01 RPMS]# ls -al /var/lib/libvirt/qemu/snapshot/mc54/
total 4
drwxr-xr-x. 2 root root 35 Oct 1 22:12 .
drwxr-xr-x. 3 qemu qemu 25 Oct 1 22:12 ..
-rw-------. 1 root root 3438 Oct 1 22:12 1412165432.xml
After insalling debian and shutting down.
[root at ovnode01 RPMS]# virsh snapshot-create mc54
Domain snapshot 1412166524 created
[root at ovnode01 RPMS]# virsh snapshot-list mc54
Name Creation
Time State
------------------------------------------------------------
1412165432 2014-10-01 22:10:32 +1000 running
1412166524 2014-10-01 22:28:44 +1000 shutoff
[root at ovnode01 RPMS]# ls -al /var/lib/libvirt/qemu/snapshot/mc54/
total 8
drwxr-xr-x. 2 root root 60 Oct 1 22:28 .
drwxr-xr-x. 3 qemu qemu 25 Oct 1 22:12 ..
-rw-------. 1 root root 3438 Oct 1 22:28 1412165432.xml
-rw-------. 1 root root 3246 Oct 1 22:28 1412166524.xml
[root at ovnode01 RPMS]# virsh snapshot-create mc44
error: unsupported configuration: internal snapshot for disk vda
unsupported for storage type raw
_Other notes_
http://ebalaskas.gr/wiki/kvm/libvirt
https://kashyapc.fedorapeople.org/virt/snapshots-notes/snapshots-with-virsh-for-qcow2.txt
2/ If you have a RAW disk image, convert your RAW image to qcow2 (with
preallocation) (NOTE: RAW format doesn't support snapshotting yet)
############## $ qemu-img convert -f raw -O qcow2 -o
preallocation=metadata /var/lib/libvirt/images/cs81test.img
/var/lib/libvirt/images/cs81test.qcow2
https://xdev.me/article/How_to_use_KVM_snapshots
http://ealkl.wordpress.com/2012/11/03/nw-proj-creating-snapshot-with-libvirt-kvm-qemu-continued/
On my quest for creating and reverting to snapshots created through
libvirt for KVM/qemu, I ended up trying to create disk-snapshot. These
are not very well supported – delete and revert of disk-snapshots
seems to unsupported through libvirt in its current version, also
disk-snapshots are not designed to store the virtual machines running
state. So these weren’t too interesting, other than the fact that I
can’t seem to loose an initial disk-snapshot that I’ve created.
This is on Ubuntu 12.10, libvirt version 0.9.5.
# The snapshot-create requires a predefined XML in place, with a name
and a description.
# In this example it is assumed there is a file called template in
your working directory.
virsh snapshot-create [domain] template.xml
# Here we parse the name and description of the snapshot through
commandline arguments:
virsh snapshot-create-as [domain] ["some name"] ["some description"]
# Revert to snapshot:
virsh snapshot-revert [domain] ["snapshot name"]
# Reverting to snapshot, you can list the available snapshot for a
given domain by running the following command:
virsh snapshot-list [domain] --tree
# Creating and reverting to a snapshot will pause your VM for the
duration. So be cautious.
===================================================================
https://github.com/autotest/virt-test/issues/152
$ virsh help snapshot-create
NAME
snapshot-create - Create a snapshot from XML
SYNOPSIS
snapshot-create [] [--redefine] [--current] [--no-metadata] [--halt]
[--disk-only] [--reuse-external] [--quiesce] [--atomic] [--live]
DESCRIPTION
Create a snapshot (disk and RAM) from XML
OPTIONS
[--domain] domain name, id or uuid
[--xmlfile] domain snapshot XML
--redefine redefine metadata for existing snapshot
--current with redefine, set current snapshot
--no-metadata take snapshot but create no metadata
--halt halt domain after snapshot is created
--disk-only capture disk state but not vm state
--reuse-external reuse any existing external files
--quiesce quiesce guest's file systems
--atomic require atomic operation
--live take a live snapshot
https://blog.gluster.org/category/virsh-snapshots/
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