Logical Domain Variable Persistence

With domaining enabled, variable updates persist across a reboot, but not across a powercycle, unless the variable updates are either initiated from OpenBoot firmware on the control domain, or followed by saving the configuration to the SC.

In this context, it is important to note that a reboot of the control domain could initiate a powercycle of the system:

• When the control domain reboots, if there are no bound guest domains, and no delayed reconfiguration in progress, the SC powercycles the system.

• When the control domain reboots, if there are guest domains bound or active (or the control domain is in the middle of a delayed reconfiguration), the SC does not powercycle the system.

LDom variables for a domain can be specified using any of the following methods:

• At the OpenBoot prompt

• Using the Solaris OS eeprom(1M) command

• Using the Logical Domains Manager CLI (ldm)

• Modifying, in a limited fashion, from the system controller (SC) using the bootmode command, that is, only certain variables, and only when in the factory-default configuration

The goal is that, variable updates that are made by using any of these methods always persist across reboots of the domain. The variable updates also always reflect in any subsequent logical domain configurations that were saved to the SC.

In LDoms 1.2 software, there are a few cases where variable updates do not persist as expected:

• With domaining enabled, all methods of updating a variable persist across reboots of that domain. However, they do not persist across a powercycle of the system, unless a subsequent logical domain configuration is saved to the SC. The methods of updating a variable include by OpenBoot firmware and by the eeprom and ldm command. Domaining is enabled by default except for the UltraSPARC T1000 and T2000 systems that run in factory-default configuration. In addition, in the control domain, updates made using OpenBoot firmware persist across a powercycle of the system, that is, even without subsequently saving a new logical domain configuration to the SC.

• When domaining is not enabled, variable updates specified through the eeprom(1M) command persist across a reboot of the primary domain into the same factory-default configuration, but do not persist into a configuration saved to the SC. Conversely, in this scenario, variable updates specified using the Logical Domains Manager do not persist across reboots, but are reflected in a configuration saved to the SC.

  So, when domaining is not enabled, if you want a variable update to persist across a reboot into the same factory-default configuration, use the eeprom command. If you want it saved as part of a new logical domains configuration saved to the SC, use the appropriate Logical Domains Manager command.

• In all cases, when reverting to the factory-default configuration from a configuration generated by the Logical Domains Manager, all LDoms variables start with their default values.

The following Bug IDs have been filed to resolve these issues: 6520041, 6540368, 6540937, and 6590259.