Oracle VM

The Oracle VM infrastructure is based on the Xen virtualization technology and Oracle own clusterware. VM images are stored as files in either a network filesystem or Oracle's cluster filesystem (OCFS2). Hypervisors are called OVM servers. A OVM manager is mandatory to create OVM server pools and to configure per-VM failover policy.

Oracle provides downloadable OVM server installation media and manager installation archives through its E-delivery website.

Oracle has a unique value proposition with OVM:

  • the billing is based on support
  • Oracle's products are certified on OVM (Oracle Linux, Solaris, database, PeopleSoft, middleware, ...)
  • Oracle provides tuned and easily instanciable VM templates for those products

The OpenSVC driver for OVM supports:

  • start, stop, migrate of virtual machines
  • HA enabled or disabled

OVM server configuration

The OVM servers may want to communicate with their manager, for example to change vms HA flag. This communication uses the ovmcli tool provided by Oracle.

Install ovmcli

Make sure you set up the following repositories in /etc/yum.conf or /etc/yum.repo.d/

[el5_addons]
name=Enterprise Linux $releasever - $basearch - addons
baseurl=http://public-yum.oracle.com/repo/EnterpriseLinux/EL5/addons/$basearch/
gpgkey=http://public-yum.oracle.com/RPM-GPG-KEY-oracle-el5
gpgcheck=1
enabled=1

[el5_oracle_addons]
name=Enterprise Linux $releasever - $basearch - oracle_addons
baseurl=http://public-yum.oracle.com/repo/EnterpriseLinux/EL5/oracle_addons/$basearch/
gpgkey=http://public-yum.oracle.com/RPM-GPG-KEY-oracle-el5
gpgcheck=1
enabled=1

Then you can install ovmcli with

yum install ovmcli

For reference, Oracle Linux public repositories are available at http://public-yum.oracle.com/public-yum-ovm2.repo

ovmcli configuration

You have to run the ovm config command one time. You will then be prompted for the manager's access information

[root@ovm2 ~]# ovm config
This is a wizard for configuring the Oracle VM Manager Command Line Interface.
CTRL-C to exit.

Oracle VM Manager hostname: ovmguest1
Oracle VM Manager port number: 4443
Deploy path (leave blank for default):
Location of vncviewer (leave blank to skip):
Enable HTTPS support? (Y/n):

Configuration complete.
Please rerun the Oracle VM Manager Command Line Interface.

Service configuration

[DEFAULT]
app = OSVC
nodes = ovm1 ovm2
orchestrate = start
env = DEV
mode = ovm

[ip#1]
ipdev = xenbr0
ipname = ovmguest1

[hb#1]
type = ovm

The hb resource instruct OpenSVC that the virtual machine must have HA enabled. In this case, manual commands on the service must be submitted using svcmgr --cluster. OpenSVC will disable HA on stop and enable HA on start.

Examples

Stop a OVM service

[root@ovm1 opensvc]# svcmgr --cluster --service ovmguest1 stop
10:52:36 INFO    OVMGUEST1.HB#1    ovm -u admin -p XXXXXX vm conf -n ovmguest1 -s pool1 -d
10:52:39 INFO    OVMGUEST1.HB#1    High availability has been disabled.

10:52:47 INFO    OVMGUEST1.OVM     xm shutdown ovmguest1
10:52:47 INFO    OVMGUEST1.OVM     wait for container down status

Start a OVM service

[root@ovm1 opensvc]# svcmgr --cluster --service ovmguest1 start
10:54:46 INFO    OVMGUEST1.OVM     xm create /var/ovs/mount/6A17B0B225C6485D8E2D03275FD3B842/running_pool/ovmguest1/vm.cfg
10:54:49 INFO    OVMGUEST1.OVM     output:
Using config file "/var/ovs/mount/6A17B0B225C6485D8E2D03275FD3B842/running_pool/ovmguest1/vm.cfg".
Started domain ovmguest1 (id=2)

10:54:49 INFO    OVMGUEST1.OVM     wait for container up status
10:54:49 INFO    OVMGUEST1.OVM     wait for container ping
10:55:22 INFO    OVMGUEST1.OVM     wait for container operational
10:55:16 INFO    OVMGUEST1.HB#1    ovm -u admin -p XXXXXX vm conf -n ovmguest1 -s pool1 -e
10:55:23 INFO    OVMGUEST1.HB#1    High availability has been enabled.

Migrate a OVM service

[root@ovm2 opensvc]# svcmgr --cluster --service ovmguest1 migrate --to ovm1
12:25:14 INFO    OVMGUEST1         exec '/usr/bin:om ovmguest1 --cluster --waitlock 60 mount' on node ovm1
12:25:19 INFO    OVMGUEST1.OVM     xm migrate -l ovmguest1 ovm1
12:26:59 INFO    OVMGUEST1         exec '/usr/bin/om ovmguest1 --cluster --waitlock 60 prstart' on node ovm1