PoC - using pre-built VM images in OST
by Marcin Sobczyk
Hi,
recently I've been working on a PoC for OST that replaces the usage
of lago templates with pre-built, layered VM images packed in RPMs [2][7].
What's the motivation?
There are two big pains around OST - first one is that it's slow
and the second one is it uses lago, which is unmaintained.
How is OST working currently?
Lago launches VMs based on templates. It actually has its own mechanism for
VM
templating - you can find the ones that we currently use here [1]. How these
templates are created? There is a multiple-page doc somewhere that
describes the process,
but few are familiar with it. These templates are nothing special really -
just a xzipped
qcow with some metadata attached. The proposition here is to replace those
templates with
RPMs with qcows inside. The RPMs themselves would be built by a CI
pipeline. An example
of a pipeline like this can be found here [2].
Why RPMs?
It ticks all the boxes really. RPMs provide:
- tried and well known mechanisms for packaging, versioning, and
distribution instead
of lago's custom ones
- dependencies which permit to layer the VM images in a controllable way
- we already install RPMs when running OST, so using the new ones is a
matter of adding
some dependencies
How the image building pipeline works? [3]
- we download a dvd iso for installation of the distro
- we use 'virt-install' with the dvd iso + kickstart file to build a 'base'
layer
qcow image
- we create another qcow image that has the 'base' image as the backing
one. In this
image we use 'virt-customize' to run 'dnf upgrade'. This is our
'upgrade' layer.
- we create two more qcow images that have the 'upgrade' image as the
backing one. On one
of them we install the 'ovirt-host' package and on the other the
'ovirt-engine'. These are
our 'host-installed' and 'engine-installed' layers.
- we create 4 RPMs for these qcows:
* ost-images-base
* ost-images-upgrade
* ost-images-host-installed
* ost-images-engine-installed
- we publish the RPMs to templates.ovirt.org/yum/ DNF repository (not
implemented yet)
Each of those RPMs holds their respective qcow image. They also have proper
dependencies
set up - since 'upgrade' layer requires 'base' layer to be functional, it
has an RPM
requirement to that package. Same thing happens for '*-installed' packages
which depend on
'upgrade' package.
Since this is only a PoC there's still a lot of room for improvement around
the pipeline.
The 'base' RPM would be actually built very rarely, since it's a bare
distro, and the
'upgrade' and '*-installed' RPMs would be built nightly. This would allow
us to simply
type 'dnf upgrade' on any machine and have a fresh set of VMs ready to be
used with OST.
Advantages:
- we have CI for building OST images instead of current, obscure template
creating process
- we get rid of lots of unnecessary preparations that are done during each
OST run
by moving stuff from 'deploy scripts' [4] to image-building pipeline -
this should
speed up the runs a lot
- if the nightly pipeline for building images is not successful, the RPMs
won't be
published - OST will use the older ones. This makes a nice "early error
detection"
mechanism and can partially mitigate situations where everything is
blocked because
of some, i.e. dependency issues.
- it's another step for removing responsibilities from lago
- the pre-built VM images can be used for much more than OST - functional
testing of
vdsm/engine on a VM? We have an image for that
- we can build images for multiple distros, both u/s and d/s, easily
Caveats:
- we have to download the RPMs before running OST and that takes time,
since they're big.
This can be handled by having them cached on the CI slaves though.
- current limitations of CI and lago force us to make a copy of the images
after
installation so they can be seen both by the processes in the chroot and
libvirt, which
is running outside of chroot. Right now they're placed in '/dev/shm'
(which would
actually make some sense if they could be shared among all OST runs on
the slave, but
that's another story). There are some possible workarounds around that
problem too (like
running pipelines on bare metal machines with libvirt running inside
chroot)
- multiple qcow layers can slow down the runs because there's a lot of
jumping around.
This can be handled by i.e. introducing a meta package that squashes all
the layers into
one.
- we need a way to run OST with custom-built artifacts. There are multiple
ways we can
approach it:
* use 'upgrade' layer and not '*-installed' one
* first build your artifacts, then build VM image RPMs that have your
artifacts
installed and pass those RPMs to OST run
* add 'ci build vms' that will do both ^^^ steps for you
Even here we can still benefit from using pre-built images - we can create
a 'deps-installed' layer that sits between 'upgrade' and '*-installed'
and contains
all vdsm's/engine's dependencies.
Some numbers
So let's take a look at two OST runs - first one that uses the old way of
working [5]
and one that uses the new pre-built VM images [6]. The hacky change that
allows us to
use the pre-built images is here [7]. Here are some running times:
- chroot init: 00:34 for the old way vs 14:03 for pre-built images
This happens because the slave didn't have the new RPMs and chroot cached,
so it took a lot
of time to download them - the RPMs are ~2GB currently. When they will be
available
in cache it will get much closer to the old-way timing.
- deployment times:
* engine 08:09 for the old way vs 03:31 for pre-built images
* host-1 05:05 for the old way vs 02:00 for pre-built images
Here we can clearly see the benefits. This is without any special fine
tuning really -
even when using pre-built images there's still some deployment done, which
can be moved
to image-creating pipeline.
Further improvements
We could probably get rid of all the funny custom repository stuff that
we're
doing right now because we can put everything that's necessary to pre-built
VM images.
We can ship the images with ssh key injected - currently lago injects an ssh
key for root user in each run, which requires selinux relabeling, which
takes a lot
of time.
We can try creating 'ovirt-deployed' images, where the whole ovirt solution
would
be already deployed for some tests.
WDYT?
Regards, Marcin
[1] https://templates.ovirt.org/repo/
[2] https://gerrit.ovirt.org/#/c/108430/
[3] https://gerrit.ovirt.org/#/c/108430/6/ost-images/Makefile.am
[4]
https://github.com/oVirt/ovirt-system-tests/tree/master/common/deploy-scr...
[5]
https://jenkins.ovirt.org/view/oVirt%20system%20tests/job/ovirt-system-te...
[6]
https://jenkins.ovirt.org/job/ovirt-system-tests_standard-check-patch/902...
[7] https://gerrit.ovirt.org/#/c/108610/
4 years
ovirt-system-tests_he-basic-suite-4.3 fails on storage domain unreachable
by Sandro Bonazzola
Debugging
https://jenkins.ovirt.org/job/ovirt-system-tests_he-basic-suite-4.3/427
on engine.log I see:
At 2020-04-28 23:48:18,378-04 I see:SetVdsStatusVDSCommandParameters:{
hostId='b34db269-5351-4653-9a0c-90a9154cd687',
status='NonOperational',
nonOperationalReason='STORAGE_DOMAIN_UNREACHABLE',
stopSpmFailureLogged='false',
maintenanceReason='null'}
So, when test try to put host1 in local maintenance at 2020-04-28
23:59:51 it fails with:
Validation of action 'MaintenanceNumberOfVdss' failed for user
admin@internal-authz. Reasons:
VAR__TYPE__HOST,VAR__ACTION__MAINTENANCE,VDS_CANNOT_MAINTENANCE_NO_ALTERNATE_HOST_FOR_HOSTED_ENGINE
vdsm on host0 shows a traceback
2020-04-28 23:43:04,944-0400 ERROR (jsonrpc/0) [vds] setKsmTune API
call failed. (API:1660)
Traceback (most recent call last):
File "/usr/lib/python2.7/site-packages/vdsm/API.py", line 1657, in setKsmTune
supervdsm.getProxy().ksmTune(tuningParams)
File "/usr/lib/python2.7/site-packages/vdsm/common/supervdsm.py",
line 56, in __call__
return callMethod()
File "/usr/lib/python2.7/site-packages/vdsm/common/supervdsm.py",
line 54, in <lambda>
**kwargs)
File "<string>", line 2, in ksmTune
File "/usr/lib64/python2.7/multiprocessing/managers.py", line 773,
in _callmethod
raise convert_to_error(kind, result)
IOError: [Errno 22] Invalid argument
which seems unrelated but maybe worth to be investigated by storage
team. +Tal Nisan <tnisan(a)redhat.com> can you look into this?
More close to the failure on host0, I see:
2020-04-28 23:49:58,775-0400 ERROR (vm/b6ca2e94) [virt.vm]
(vmId='b6ca2e94-df8b-48e9-b0ee-2bc0f939786a') The vm start process
failed (vm:934)
Traceback (most recent call last):
File "/usr/lib/python2.7/site-packages/vdsm/virt/vm.py", line 868,
in _startUnderlyingVm
self._run()
File "/usr/lib/python2.7/site-packages/vdsm/virt/vm.py", line 2895, in _run
dom.createWithFlags(flags)
File "/usr/lib/python2.7/site-packages/vdsm/common/libvirtconnection.py",
line 131, in wrapper
ret = f(*args, **kwargs)
File "/usr/lib/python2.7/site-packages/vdsm/common/function.py",
line 94, in wrapper
return func(inst, *args, **kwargs)
File "/usr/lib64/python2.7/site-packages/libvirt.py", line 1110, in
createWithFlags
if ret == -1: raise libvirtError ('virDomainCreateWithFlags()
failed', dom=self)
libvirtError: internal error: qemu unexpectedly closed the monitor:
2020-04-29T03:49:55.484660Z qemu-kvm: warning: All CPU(s) up to
maxcpus should be described in NUMA config, ability to start up with
partial NUMA mappings is obsoleted and will be removed in future
2020-04-29T03:49:55.582536Z qemu-kvm: -device
virtio-blk-pci,iothread=iothread1,scsi=off,bus=pci.0,addr=0x7,drive=drive-ua-cfb2266f-5d47-4418-b30f-9c1d3fbf512c,id=ua-cfb2266f-5d47-4418-b30f-9c1d3fbf512c,bootindex=1,write-cache=on:
Failed to get shared "write" lock
Is another process using the image
[/var/run/vdsm/storage/fc1a55d5-deb4-4423-be56-e7313645798b/cfb2266f-5d47-4418-b30f-9c1d3fbf512c/68d04a61-9f34-4a1b-8d6e-bca43a7b9339]?
2020-04-28 23:49:58,775-0400 INFO (vm/b6ca2e94) [virt.vm]
(vmId='b6ca2e94-df8b-48e9-b0ee-2bc0f939786a') Changed state to Down:
internal error: qemu unexpectedly closed the monitor:
2020-04-29T03:49:55.484660Z qemu-kvm: warning: All CPU(s) up to
maxcpus should be described in NUMA config, ability to start up with
partial NUMA mappings is obsoleted and will be removed in future
2020-04-29T03:49:55.582536Z qemu-kvm: -device
virtio-blk-pci,iothread=iothread1,scsi=off,bus=pci.0,addr=0x7,drive=drive-ua-cfb2266f-5d47-4418-b30f-9c1d3fbf512c,id=ua-cfb2266f-5d47-4418-b30f-9c1d3fbf512c,bootindex=1,write-cache=on:
Failed to get shared "write" lock
Is another process using the image
[/var/run/vdsm/storage/fc1a55d5-deb4-4423-be56-e7313645798b/cfb2266f-5d47-4418-b30f-9c1d3fbf512c/68d04a61-9f34-4a1b-8d6e-bca43a7b9339]?
(code=1) (vm:1702)
2020-04-28 23:49:58,799-0400 INFO (vm/b6ca2e94) [virt.vm]
(vmId='b6ca2e94-df8b-48e9-b0ee-2bc0f939786a') Stopping connection
(guestagent:455)
2020-04-28 23:49:58,849-0400 INFO (jsonrpc/1) [api.virt] START
destroy(gracefulAttempts=1) from=::ffff:192.168.200.99,49938,
vmId=b6ca2e94-df8b-48e9-b0ee-2bc0f939786a (api:48)
2020-04-28 23:49:58,851-0400 INFO (jsonrpc/1) [virt.vm]
(vmId='b6ca2e94-df8b-48e9-b0ee-2bc0f939786a') Release VM resources
(vm:5186)
2020-04-28 23:49:58,851-0400 WARN (jsonrpc/1) [virt.vm]
(vmId='b6ca2e94-df8b-48e9-b0ee-2bc0f939786a') trying to set state to
Powering down when already Down (vm:626)
2020-04-28 23:49:58,851-0400 INFO (jsonrpc/1) [virt.vm]
(vmId='b6ca2e94-df8b-48e9-b0ee-2bc0f939786a') Stopping connection
(guestagent:455)
+Ryan Barry <rbarry(a)redhat.com> can you check the qemu-kvm warning?
Help understanding why storage domain became unreachable is welcome.
--
Sandro Bonazzola
MANAGER, SOFTWARE ENGINEERING, EMEA R&D RHV
Red Hat EMEA <https://www.redhat.com/>
sbonazzo(a)redhat.com
<https://www.redhat.com/>*
<https://www.redhat.com/en/summit?sc_cid=7013a000002D2QxAAK>*
*Red Hat respects your work life balance. Therefore there is no need to
answer this email out of your office hours.*
4 years
ovirt-imageio image upload feedback on engine 4.4.0-31
by Guilherme De Oliveira Santos
Hi people,
I recently had to upload an image on a 4.4.0-31 engine and Nir told me to
share here the feedback.
I installed ovirt-imageio-common-2.0.5-0.el8ev.x86_64
and created the following script to upload it using sdk:
#!/usr/bin/bash
python3 /root/ovirt-engine-sdk/sdk/examples/upload_disk.py \
--engine-url "https://`hostname`/" \
--username admin@internal \
--password-file pssword \
--cafile /tmp/ca.pem \
--disk-format qcow2 \
--disk-sparse \
--sd-name nfs_0 \
/tmp/rhel-guest-image-7.6-210.x86_64.qcow2
The image got uploaded pretty quickly and I didn't have any trouble...
Cheers,
Gui
4 years
engine-setup failing on restarting ovirt-imageio
by Sandro Bonazzola
Failing job is https://jenkins.ovirt.org/job/ovirt-system-tests_manual/6794/
Here's the relevant log in engine-setup:
2020-04-27 09:25:35,457-0400 DEBUG
otopi.plugins.otopi.services.systemd plugin.executeRaw:813 execute:
('/usr/bin/systemctl', 'stop', 'ovirt-imageio.service'),
executable='None', cwd='None', env=None
2020-04-27 09:25:35,652-0400 DEBUG
otopi.plugins.otopi.services.systemd plugin.executeRaw:863
execute-result: ('/usr/bin/systemctl', 'stop',
'ovirt-imageio.service'), rc=0
2020-04-27 09:25:35,653-0400 DEBUG
otopi.plugins.otopi.services.systemd plugin.execute:921
execute-output: ('/usr/bin/systemctl', 'stop',
'ovirt-imageio.service') stdout:
2020-04-27 09:25:35,653-0400 DEBUG
otopi.plugins.otopi.services.systemd plugin.execute:926
execute-output: ('/usr/bin/systemctl', 'stop',
'ovirt-imageio.service') stderr:
2020-04-27 09:25:35,653-0400 DEBUG
otopi.plugins.otopi.services.systemd systemd.state:170 starting
service ovirt-imageio
2020-04-27 09:25:35,654-0400 DEBUG
otopi.plugins.otopi.services.systemd plugin.executeRaw:813 execute:
('/usr/bin/systemctl', 'start', 'ovirt-imageio.service'),
executable='None', cwd='None', env=None
2020-04-27 09:25:36,631-0400 DEBUG
otopi.plugins.otopi.services.systemd plugin.executeRaw:863
execute-result: ('/usr/bin/systemctl', 'start',
'ovirt-imageio.service'), rc=1
2020-04-27 09:25:36,632-0400 DEBUG
otopi.plugins.otopi.services.systemd plugin.execute:921
execute-output: ('/usr/bin/systemctl', 'start',
'ovirt-imageio.service') stdout:
2020-04-27 09:25:36,632-0400 DEBUG
otopi.plugins.otopi.services.systemd plugin.execute:926
execute-output: ('/usr/bin/systemctl', 'start',
'ovirt-imageio.service') stderr:
Job for ovirt-imageio.service failed because the control process
exited with error code.
See "systemctl status ovirt-imageio.service" and "journalctl -xe" for details.
2020-04-27 09:25:36,633-0400 DEBUG otopi.context
context._executeMethod:145 method exception
Traceback (most recent call last):
File "/usr/lib/python3.6/site-packages/otopi/context.py", line 132,
in _executeMethod
method['method']()
File "/usr/share/ovirt-engine/setup/bin/../plugins/ovirt-engine-setup/ovirt_imageio/config.py",
line 190, in _closeup_resatrt_service
state=state,
File "/usr/share/otopi/plugins/otopi/services/systemd.py", line 181, in state
service=name,
RuntimeError: Failed to start service 'ovirt-imageio'
2020-04-27 09:25:36,636-0400 ERROR otopi.context
context._executeMethod:154 Failed to execute stage 'Closing up':
Failed to start service 'ovirt-imageio'
--
Sandro Bonazzola
MANAGER, SOFTWARE ENGINEERING, EMEA R&D RHV
Red Hat EMEA <https://www.redhat.com/>
sbonazzo(a)redhat.com
<https://www.redhat.com/>*
<https://www.redhat.com/en/summit?sc_cid=7013a000002D2QxAAK>*
*Red Hat respects your work life balance. Therefore there is no need to
answer this email out of your office hours.*
4 years
Uploading iso / ovirt-imageio
by Artur Socha
Hi,
After a long break I am trying setup my engine so that I could upload images
(ISO) there and use them when spinning new VMs. First I tried recent master
(FC31) and then latest 4.4 beta from RPMs (Centos8).
I have ovirt-imageio daemon running on the same host engine is running. (with
the simplest possible configuration - TLS disabled)
Unfortunately when I hit 'test connection' in admin ui/storage/domain I keep
seeing error message complaining about ovirt-imageio-proxy setup.
I know that recently there has been quite a lot of changes related to the next
version of imageio.
Is there something else besides ovirt-imageio daemon that I should have
installed/configured? Perhaps there is some documentation I could use?
thanks!
--
Artur Socha
Senior Software Engineer, RHV
Red Hat
4 years
Backup is not supported by the host, Ovirt 4.4 Beta
by francesco＠shellrent.com
Hi all,
I'm trying to experiment with incremental backup using the example script provided on sdk git page (https://github.com/oVirt/ovirt-engine-sdk/blob/master/sdk/examples/backup...). I installed a fresh engine on a CentOS 8 VM and installed a fresh node on CentOS 8 as well, connected to the engine without any problems. All libvirt packages version 5.6 and ovirt-imageio-common version 2.0.3 .
Passing all the needed args to the script (I hardcoded connections var like user and password) it throws the following error:
```
[root@centos8 ~]# python3 backup_vm.py full --engine-url https://ovirt-engine-fqdn.com --username admin@internal --password-file ./passwd --backup-dir /home 11d70eb0-4d7c-4308-82a6-470e21d80ecd
[ 0.0 ] Starting full backup for vm 11d70eb0-4d7c-4308-82a6-470e21d80ecd
Traceback (most recent call last):
File "backup_vm.py", line 397, in <module>
main()
File "backup_vm.py", line 141, in main
args.command(args)
File "backup_vm.py", line 154, in cmd_full
backup = start_backup(connection, args)
File "backup_vm.py", line 247, in start_backup
disks=disks
File "/usr/lib64/python3.6/site-packages/ovirtsdk4/services.py", line 33583, in add
return self._internal_add(backup, headers, query, wait)
File "/usr/lib64/python3.6/site-packages/ovirtsdk4/service.py", line 232, in _internal_add
return future.wait() if wait else future
File "/usr/lib64/python3.6/site-packages/ovirtsdk4/service.py", line 55, in wait
return self._code(response)
File "/usr/lib64/python3.6/site-packages/ovirtsdk4/service.py", line 229, in callback
self._check_fault(response)
File "/usr/lib64/python3.6/site-packages/ovirtsdk4/service.py", line 132, in _check_fault
self._raise_error(response, body)
File "/usr/lib64/python3.6/site-packages/ovirtsdk4/service.py", line 118, in _raise_error
raise error
ovirtsdk4.Error: Fault reason is "Operation Failed". Fault detail is "[Cannot backup VM. Backup is not supported by the host (centos8).]". HTTP response code is 409.
```
The VM is created from centOS 7 template imported from ovirt-image-repository, and the options "Enable Incremental Backup" on the disk is ticked.
I'm definitely missing something... But what? On the top of the script, I read "Using this example requires a special libvirt version supporting
incremental backup.". Which version of libvirt? I guessed the 5.6 (or at least not the 4.5 shipped in CentOS 7).
Thank you for your time and help,
Francesco
4 years
