This article is regarding an issue we originally blogged about over at The Configuration Manager Support Team Blog regarding issues with PXE booting caused by duplicate SMBIOS GUIDs.. At the time that we wrote the article we really didn’t have a good solution or workaround on the ConfigMgr/WDS side to fix the issue. Since the issue was a problem caused by an OEM not adhering to industry standards, the only recommendation we could make was contacting the OEM for a fix at the hardware level.
Although the recommendation is to still fix the root cause of the issue by obtaining and running a fix from the OEM, we have recently discovered a feature of WDS called BannedGUIDs that allows us to work around the issue. This is especially useful in environments where there may be a large amount of duplicate SMBIOS GUIDs or where a BIOS fix or utility is not currently available from the OEM vendor. The below article outlines the issue and how to use the WDS workaround.
Note: We are planning to publish the below article as a KB article. If not already available, it should be available soon as KB2591483.
No Assigned Task Sequence when initiating deployments caused by duplicate SMBIOS GUIDs (System UUIDs) in System Center Configuration Manager 2007
When trying to start a ConfigMgr 2007 OSD Task Sequence on a PC, ConfigMgr fails to find a Task Sequence to run on the PC.
- If booting from boot media, the follow message well appear after booting into WinPE:
There are no task sequences available for this computer.
Examining the SMSTS.log obtained from X:WindowsTempSMSTSLog will show the following message:
No assigned task sequence. TSMBootstrap
Setting wizard error: There are no task sequences available for this computer. TSMBootstrap
- If booting from PXE, the PXE boot screen will show the following message:
TFTP Download: smsboot<arch>abortpxe.com
PXE Boot aborted. Booting to the next device…
The SMSPXE.log on the PXE Service Point server will contain the following messages at the time the PXE boot was attempted:
MAC=<Mac_Address> SMBIOS GUID=<SMBIOS_GUID> > Device found in the database. MacCount=x GuidCount=y smspxe
ProcessDatabaseReply: No Advertisement found in Db for device smspxe
If the PC is Known (either an existing client or prestaged via the Import Computer Information Wizard), it has been verified that the Task Sequence Advertisement is targeted to a Collection that the PC is a member of.
If the PC is Unknown, it has been verified that the Task Sequence Advertisement is targeted to a Collection with the Unknown Computer objects (x64 Unknown Computer and/or x86 Unknown Computer) and that the PC is truly unknown and does not exist in the ConfigMgr database.
This problem can be caused by more than one PC in the environment having the same SMBIOS GUID. ConfigMgr refers the SMSBIOS GUID as System UUID. Similar to a MAC Addresses being unique to a NIC card, the SMBIOS GUIDs should also be unique on each PC. Two PCs should not have the same SMBIOS GUID. The SMBIOS GUID is stored in the PC’s BIOS.
The problem occurs because when the ConfigMgr database is queried for available Task Sequence that are advertised to that PC, it does so first by using the PC’s SMBIOS GUID. Each record in the ConfigMgr database records the PC’s SMBIOS GUID under the attribute System UUID. If it does not match a record with the SMBIOS GUID, it then uses the MAC Address instead.
However, if multiple PCs have the same SMBIOS GUID in the environment, when the query on the SMBIOS GUID is done on the ConfigMgr database, it may find the record for a PC other than the one that the Task Sequence is advertised to. If the Task Sequence is not also advertised to the PC that it found, it will return back that there are no task sequences available for the computer.
NOTE: Do not confuse the SMBIOS GUID with the SMS GUID. They are two separate, different, and distinct items. The SMBIOS GUID is a unique hardware identifier used universally, whereas the SMS GUID is a unique ConfigMgr client ID used exclusively by SMS/ConfigMgr.
To see if the problem exists in the environment, create a query or collection in ConfigMgr based on the suspected duplicate SMBIOS GUID using the System UUID attribute. If more than one PC has the same SMBIOS GUID, then the problem exists.
To obtain the SMBIOS GUID from a PC having the problem, use one of the below methods:
- At a command prompt, run the command:
When the prompt
appears, type in the command:
csproduct get uuid
The SMBIOS GUID for the PC should be displayed.
Please note that in scenarios where the PC does not have a bootable OS, the PC can be boot into WinPE via PXE or boot media, and then the above commands run from a command prompt window running in WinPE.
- On most PCs the SMBIOS GUID appears next to GUID: at the PXE boot screen. To pause the PXE boot screen so that the SMBIOS GUID can be copied down, hit the Pause/Break key on the keyboard while at the PXE boot screen. This can be done even if a PXE server does not exist in the environment. However to view the PXE boot screen, PXE booting must be enabled in the BIOS of the PC and either F12 may need to be hit to get to the PXE boot screen or the NIC may need to be temporarily set as the first boot device on the PC.
- For PCs that successfully boots into WinPE from boot media but fails to receive an advertised Task Sequence, the SMBIOS GUID will be displayed in the SMSTS.log next to the line
Setting SMBIOS GUID =
- For PCs that do not successfully boot from PXE, the SMSPXE.log on the server hosting the PXE Service Point can be examined for the PC’s SMBIOS GUID. The line that contains this information will be something as follows:
MAC=<Mac_Address> SMBIOS GUID=<SMBIOS_GUID> > Device found in the database. MacCount=x GuidCount=y
Note: Ignore the lines in the SMSPXE.log with all Fs for the MAC Address:
MAC=FF:FF:FF:FF:FF:FF:FF:FF:FF:FF:FF:FF:FF:FF:FF:FF SMBIOS GUID=<SMBIOS_GUID> > Device not found in the database. smspxe
These lines are the PXE Service Point performing a self-check on itself by performing a PXE request to itself to make sure the PXE Service Point is up and operational.
To create a query based Collection that finds all PCs with a particular SMBIOS GUID:
- In the ConfigMgr console, navigate to “Site Database” –> “Computer Management” –> “Collections“
- Right click on “Collections” and choose “New Collection“
- On the “General” page of the “New Collection Wizard“, give the Collection a name next to the “Name:” textbox and then click on the “Next >” button.
- On the “Membership Rules” page of the “New Collection Wizard“, click on the yellow Query icon.
- Under the “General” tab of the “Query Rule Properties” window, give the query a name next “Name:” textbox and then click on the “Edit Query Statement…” button.
- In the “Query Statement Properties” window, click on the “Criteria” tab, and then click on the yellow starburst button.
- In the “Criterion Properties” window, make sure that the “Criterion Type:” is set to “Simple value” and then click on the “Select…” button.
- In the “Select Attribute” window:
- Next to “Attribute class:“, select “System Resource“
- Next to “Alias as:“, leave at the default of “<No Alias>“
- Next to “Attribute:“, choose “System UUID“
- Next to “Attribute class:“, select “System Resource“
- In the “Select Attribute” window, click on the “OK” button.
- In the “Criterion Properties” window, make sure that the “Operator:” is set to “is equal to“.
- In the “Criterion Properties” window, next to the “Value:” text box, enter in the full SMBIOS GUID obtained from the PC. Make sure to enter all 32 characters and the 4 dashes that are part of the SMBIOS GUID.
- In the “Criterion Properties” window, click on the “OK” button.
- In the “Query Statement Properties” window, click on the “OK” button.
- In the “Query Rule Properties” window, click on the “OK” button.
- On the “Membership Rules” page of the “New Collection Wizard“, click on the “Next >” button.
- On the “Advertisements” page of the “New Collection Wizard“, click on the “Next >” button.
- On the “Security” page of the “New Collection Wizard“, click on the “Next >” button.
- When the “New Collection Wizard” completes, click on the “Close” button.
The newly created Collection should display all of the PCs affected by the duplicate SMBIOS GUID. Repeat the above steps if more than one set of duplicate SMBIOS GUIDs exist in the environment.
Please note that this problem is caused by an OEM vendor not adhering to industry standards. It is not an issue with ConfigMgr.
There are two possible solutions to the problem
- Obtain a BIOS update or utility from the OEM hardware vendor that fixes the duplicate SMBIOS GUIDs and gives each PC a unique SMBIOS GUID.
- To work around the problem, use the BannedGUIDsregistry entry of WDS as described in the following TechNet articles:
Windows Deployment Services Registry Entries
How PXE Requests Work
The BannedGUIDs registry entry “ignores” any SMBIOS GUIDs that have been entered under the key and instead uses the PC’s MAC Address.
Please note that this solution does not actually fix the root cause of the problem and only works around it. When possible, it is recommended to use Solution #1. However in environments where there may be a large amount of duplicate SMBIOS GUIDs or where a BIOS fix or utility is not currently available from the OEM vendor, the BannedGUIDs registry can be used to work around the issue until the duplicate GUIDs issue can be permanently resolved.
For both solutions, use the methods described in the Cause section to discover what PCs are affected by duplicate SMBIOS GUIDs.