Users Guide

Related concepts
Summary of Supported Features for Storage Devices
Supported Enclosures
Configuring Backplane Mode
Viewing Universal Slots
Setting SGPIO Mode
Configuring Backplane Mode
The 13th generation Dell PowerEdge servers supports a new internal storage topology, where two storage controllers (PERCs) can be
connected to a set of internal drives through a single expander. This configuration is used for high performance mode with no failover or
High Availability (HA) functionality. The expander splits the internal drive array between the two storage controllers. In this mode, virtual
disk creation only displays the drives connected to a particular controller. There are no licensing requirements for this feature. This feature
is supported only on a few systems.
Backplane supports two modes:
• Unified mode — The primary PERC controller has access to all the drives connected to the backplane even if a second PERC
controller is installed.
• Split mode — One controller has access to the first 12 drives and the second controller has access to the last 12 drives. This splitting is
not configurable. The drives connected to the first controller are numbered 0-11 while the drives connected to the second controller
are numbered 12-23.
By default, it is in unified mode.
iDRAC allows the split mode setting if the expander has the capability to support the configuration. You may want to enable this mode
prior to installing the second controller. iDRAC performs a check for expander capability prior to allowing this mode to be configured and
does not check whether the second PERC controller is present.
To modify the setting, you must have Server Control privilege.
If any other RAID operations are in pending state or any RAID job is scheduled, you cannot change the backplane mode. Similarly, if this
setting is pending, you cannot schedule other RAID jobs.
NOTE:
• Warning messages are displayed when the setting is being changed as there is a possibility of data loss.
• LC Wipe or iDRAC reset operation does not change the expander setting for this mode.
• This operation is supported only in real-time and not staged.
Any change in this setting only takes effect after a system power reset. If you change from Split mode to Unified, an error message is
displayed on the next boot as the second controller does not see any drives. Also, the first controller will see a foreign configuration. If you
ignore the error, the existing virtual disks are lost.
Configuring Backplane Mode Using Web Interface
To configure backplane mode using iDRAC Web interface:
1. In the iDRAC Web interface, go to Overview > Storage > Enclosures > Setup
The Enclosure Setup page is displayed.
2. From the Controller drop-down menu, select the controller to configure its associated enclosures.
3. In the Value column, select the required mode for the required backplane or enclosure:
• Unified
• Split
4. From the Apply Operation Mode drop-down menu, select Apply Now to apply the actions immediately, and then click Apply.
A job ID is created.
5. Go to the Job Queue page and verify that it displays the status as Completed for the job.
6. Power cycle the system for the setting to take affect.
Configuring Enclosure Using RACADM
To configure the enclosure or backplane, use the BackplaneMode object with the set subcommand.
For example, to set the BackplaneMode attribute to split mode:
Managing Storage Devices
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