Visa källa för 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

[[Fil:Oracle-OVM-Pic.jpg]]

==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 Hyerpvisor 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 for instances on Hypervisor OVM host===
 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.

=== Useful commands for instances on OS OVM-host===
 zoneadm list -icv  <-- View all of zones configured on the host
 zoneadm -z  <zonename> boot/reboot/halt
 zonecfg -z  <zonename> info  <--display zones configuration
 zonecfg -z <zonename> export  <-- export zone configuration to file
 zlogin <zonename>  <--login to a zone
 zlogin -C <zonename>  <-- login to zone's console