The following sections describe restrictions for domain migration. The Logical Domains Manager software and the system firmware versions must be compatible to permit migrations. Also, you must meet certain CPU requirements to ensure a successful domain migration.
Live migration is not qualified and supported on all combinations of the source and target platforms and system firmware versions. For those combinations that cannot perform a live migration, you can perform a cold migration instead.
This section describes version restrictions for performing live migrations.
Logical Domains Manager version. You can perform a live migration in either direction when one system runs the latest version of the Logical Domains Manager and the other system runs at least the immediately preceding version of the Logical Domains Manager.
Oracle Solaris OS version. You can perform a live migration of a guest domain that runs at least the Oracle Solaris 10 9/10 OS. You cannot perform a live migration of a guest domain that runs the Oracle Solaris 10 10/09 OS or earlier Oracle Solaris OS versions. You can still boot these older Oracle Solaris OS versions and perform cold migrations of such domains.
System firmware version. In general, you can perform a live migration between two systems when both the source and target machines support the appropriate minimum system firmware versions. See Minimum System Firmware Versions in Oracle VM Server for SPARC 3.4 Installation Guide.
You cannot perform live migration operations between an UltraSPARC T2, UltraSPARC T2 Plus, or SPARC T3 server and servers starting with the SPARC T5 server.
Take care when performing migrations of domains that have the perf-counters property value set.
Before you perform the migration of a domain that has the perf-counters property value set to global, ensure that no other domain on the target machine has the perf-counters property set to global.
During a migration operation, the perf-counters property is treated differently based on whether the performance access capability is available on the source machine, the target machine, or both.
The perf-counters property value is treated as follows:
Source machine only. The perf-counters property value is not propagated to the target machine.
Target machine only. The perf-counters property value on the machine to be migrated is updated to be equivalent to perf-counters=.
Source and target machines. The perf-counters property value is propogated from the domain to be migrated to the migrated domain on the target machine.
For more information about the perf-counters property, see Using Perf-Counter Properties and the ldm(1M) man page.
You can migrate a virtual network device that has a physical NIC backing device and has linkprop=phys-state to a target domain that does not have a physical NIC as a backing device (net-dev=). Because the linkprop=phys-state constraint is not a hard requirement, if such a domain is migrated to a machine that does not have an available net-dev value, the constraint is preserved but not fulfilled. The linkprop property is still preserved as phys-state and the network device link state shows as link up.
Sometimes, migrating a domain that has a large number of virtual devices causes the control domain on the target machine to be less responsive than usual. During this time, ldm commands appear to hang and standard Oracle Solaris OS commands take longer to complete than usual.
This interruption is caused by virtual servers processing the large number of incoming virtual devices associated with the migrated domain. After this processing completes, the control domain returns to normal and any stalled ldm commands complete.
You can minimize this sort of interruption by limiting the number of virtual devices used by a domain to no more than 1000.