Oracle-OVM

Oracle OVM

There are several types of virtualisation for Solaris which are covered by this generic name OVM (Oracle Virtual Machine)

- Hypervisor

Oracle LDOMs

- OS

Solaris Zones/Containers either a Whole, Sparse or Kernel version

General Information

OVM is included in Solaris 11 and Solaris 10 It does not require a RTU licence although a Support contract for each running guest domain will be required. The advantages for OVM are:

- provision bare metal hypervisors

- provision virtual machines

- Hard Partitioning. Oracles licence structure for Mulit-core & Multi-threaded environments. To avoid paying for all the cores in the platform hard partitioning is configured to licence just the cores that are used in the virtual instance.

• • This is enforced by using CPU whole-core configurations.
  • A CPU whole-core configuration has domains that are allocated CPU whole cores instead of individual CPU threads.
  • When binding a domain in a whole-core configuration, the system provisions the specified number of CPU cores and all its CPU threads to the domain.
  • Using a CPU whole-core configuration limits the number of CPU cores that can be dynamically assigned to a bound or active domain.

NB! By default, a domain is configured to use CPU threads.

- migrate virtual machines to different hosts either "Warm" or "Cold" migration.

- Guest domains can run Solaris 11 or Solaris 10. Zones can be then configured in the guest domain.

NB! this will though limit that guest domain to cold migration only

- ZFS on host domain allows for easy patch and backup/recovery policy.

- NFS volumes or SAN disk/iSCSI with cluster file-system to facilitate "Warm" migration.

For best practice migrtation the architecture requires the following components:

• A shared filesystem for hosting virtual machines to allow for node migration.
  • Cold Migration involves stopping, manual migration and start of LDOM.
  • Warm Migration allows for automatic migration with minimal downtime for the migration.

Having this shared file system (which we recommend be on a SAN, iSCSI (med Cluster FS) or GPFS allows us migrate nodes from).

• • Solaris 10 (11/13) & 11 LDOMs
  • Solaris 8,9 & 10 zones

- Running an < init 5 > on a primary domain with running guest domains will reboot the primary domain i.e it will act as an < init 6 >

OVM administration

• List all nodes running on a OVM-host

ldm ls

NAME             STATE      FLAGS   CONS    VCPU  MEMORY   UTIL  NORM  UPTIME
primary          active     -n-cv-  UART    2     16G      1.5%  1.5%  84d 34m
guest-dom        active     -n----  5001    16    28G      0.4%  0.4%  84d 29m

• Start/Stop a guest domain

ldm start <guest-domain>
ldm stop <guest-domain>

• Useful commands

ldm   <- display help for ldm
ldm list-services  <-- display assigned disk, net, cpu etc...
ldm list-constraints  <-- display cpu cores, max-cores etc...
ldm list-variable <domain>   <-- display boot params for domain
ldm list -o resmgmt <domain>  <-- determine if domain configured with whole-cores for hard partitioning.