Configuring LDoms systems to use a graphics adapter as the console device will find functionality inconsistent with previous SPARC platforms.

Asset ID:	1-73-1018990.1
Update Date:	2010-09-16
Keywords:

Solution Type FAB (standard) Sure

Solution 1018990.1 : Configuring LDoms systems to use a graphics adapter as the console device will find functionality inconsistent with previous SPARC platforms.

Impact

Console behavior is inconsistent when a graphics device and keyboard are specified for console use. This occurs when the OpenBoot variables 'input-device' and 'output-device' are set to anything other than the default value of 'virtual-console'.

If the system is put in such a state, some console messages are sent to the graphics console and others are sent to the virtual console. This results in incomplete information on either console. In addition, when the system is halted, or a break is sent to the console, control is passed to the virtual console. As a result, the graphics console appears to hang.

Contributing Factors

Any system running CoolThreads may be impacted by this issue.

Logical Domains (LDoms) was not designed to support graphics adapters and USB keyboards/mice for console I/O. A domain's console is through the LDom's Virtual Console Concentrator accessible via network or the SP's serial port.

Configuring Solaris to use a device or devices other than the Virtual Console Concentrator will result in an inconsistent management experience for the Customer.

Logical Domains is Sun's own virtualization technology which allows multiple, independently bootable OS instances to run on a single machine. Reference the below URL for more information on this technology:

http://www.sun.com/servers/coolthreads/ldoms/

Note: LDoms is enabled by default on SPARC Enterprise T5120/T5220 and follow-on platforms.

Symptoms

Boot:

During the early stages of boot, console output will appear on the graphics console then silently switch to the virtual console. Viewing the graphics console the system will have appeared to hang, but this is not the case. The boot sequence continues normally with the virtual console as the input and output device.

Halt:

Instead of proceeding directly to the OBP OK prompt, Solaris presents the following sun4v prompt on the virtual console:

   r)eboot, o)k prompt, h)alt?

This prompt is expecting a reply on the virtual console. Viewing the system from the graphics console, the system will have appeared to hang.

Break:

Issuing a Break, Solaris present in place of the OBP OK prompt, the following sun4v prompt on the virtual console:

   c)ont, s)ync, r)eboot, h)alt?

This prompt is expecting a reply on the virtual console. When using Kernel Modular Debugger (KMDB) the console device is forced to be the virtual console. Viewing the system from the graphics console, the system will have appeared to hang.

Root Cause

All versions of the LDoms product dismiss OBP when Solaris is ready to standalone. In versions prior to LDoms 1.1, the dismissal of OBP occurred before the Solaris console redirection framework could finish replumbing.

Actions such Halt and Break which would have been serviced by OBP instead go to the sun4v prompting logic. This logic is fixed to present its output and take its input on the virtual console.

Corrective Action

Workaround

In order to avoid this issue only the virtual console should be used. From OpenBoot, ensure that the default value of 'virtual-console' is set for both the 'input-device' and 'output-device' variables.

Once the graphics console appears hung, one must connect to the virtual console from the System Processor in order to provide the required input. Press carriage return on the virtual console keyboard once to see the output on the virtual console.

Resolution

LDoms version 1.1 and later support console redirection, including Keyboard, Video, Mouse (KVM) devices. In the KVM case, video adapter support is limited to those devices whose drivers are compatible with Solaris's Coherent Console framework.

A KVM, also called a "KVM switch", allows a single keyboard, monitor and mouse to be shared (connected to) multiple machines. The user can use the switch to control which system the i/o devices are "talking to" at any given time. These KVM switches are third party devices.

These changes will be released in the below Solaris S10U5 patch, scheduled for release mid-June of 2008.

137111-01 # the kernel patch

The following patch is required for systems which are configured with the XVR-300 graphics card:

124149-09 (or higher)

For information about FAB documents, its release processes, implementation strategies and billing information, go to the following URL:

http://tns.central/fab

For Sun Authorized Service Providers go to:

http://tns.central/SPE/fab/

In addition to the above you may email:

[email protected]

Internal Contributor/submitter
[email protected]

Internal Eng Responsible Engineer
[email protected] Responsible Manager: [email protected]

Internal Services Knowledge Engineer
[email protected]

Internal Eng Business Unit Group
SSG SW (Platform Software)

Internal Sun Alert & FAB Admin Info
08-Feb-2008: Initial draft completed and sent to Extended Review.
12-Feb-2008: Awtg Submitter response to Ext Rvw feedback.
15-Feb-2008: Resolved feedback - IBIS is down or unstable at this time.
17-Feb-2008: FAB sent to Publish.
16-May-2008: Added references to two patches in Resolution section.
06-Jan-2009: Corrected Product Name to swoRDFish inconsistency.

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