Unmanaged Persistent Storage; Figure 20. Internal Dual Sd Module Shown With A Single Card - Dell External OEMR R810 Technical Manual

Dell

Life Cycle Log (2 MB): stores initial factory configuration as well as all detectable hardware
and firmware changes to the server since its deployment. The Life Cycle Log is stored on the
BMC SPI flash.
Approximately 20% of the flash space is reserved for wear leveling on the NAND flash. Wear leveling
is a method designed to extend the life of the NAND flash by balancing the use cycles on the flash's
blocks.
12.2.2

Unmanaged Persistent Storage

123B
12.2.2.1 General
128B
The unmanaged persistent storage consists of two options: one located on the control panel board
and one located on the Internal Dual SD Module. The port on the control panel is for an optional USB
key and is located inside the chassis. Some of the possible applications of the USB key are:

User custom boot and pre-boot OS for ease of deployment or diskless environments

USB license keys for software applications

Storage of custom logs or scratch pad for portable user-defined information (not hot-
pluggable)
12.2.2.2 Internal Dual SD Module
129B
The Internal Dual SD Module was developed in response to customer concerns about single-SD-card
based embedded hypervisor potentially being a single point of failure. Dell designed a fully
redundant module which uses two SD cards in a fully mirrored mode. If one card fails, the module
issues an alert (no longer redundant) and continues to function with the surviving SD card. This
allows the customer to gracefully bring down the hardware node to restore redundancy without any
interruption to the supported virtual machines (VMs).

Figure 20. Internal Dual SD Module Shown with a Single Card

Dell PowerEdge R810 Technical Guide 45