Dell POWERVAULT MD1000 - Manual (Page 14)

14 About Your System
Unified Mode and Split Mode
The enclosure can run in one of two modes:
• Unified
• Split
In unified mode, a SAS host can communicate with up to 15 drives in the enclosure via a single EMM, or
up to 45 drives in three enclosures daisy chained together. In split mode, the enclosure is split into two
virtual groups, with up to eight consecutive drives (slots 7-14) controlled by the primary (left) EMM. The
remaining drives (slots 0-6) are controlled by the secondary (right) EMM. You must select either mode
using the enclosure mode switch on the front panel of the enclosure before powering on (see Figure 1-7).
NOTE: Clustering is not supported in the MD1000 host-based RAID solution.
Figure 1-6 illustrates the division of control, depending on whether you select the enclosure to run in
either unified or split mode.
6 EMM Status LED
(green/amber)
Solid green: EMM is functioning properly.
Solid amber: The enclosure did not boot or was not
properly configured.
Off: EMM did not boot, is not properly configured,
or communication between the EMM and the
server is lost.
Green flashing (250 ms): Firmware download in
progress.
Amber flashing (On 250 ms Off 250 ms [once];
Off 1000 ms): Communication between SAS
expanders and enclosure processor could not be
established.
Amber flashing (On 250 ms Off 250 ms [twice];
Off 1000 ms): Enclosure processor unable to
communicate with enclosure devices.
Amber flashing (On 250 ms Off 250 ms [three
times]; Off 1000 ms): One or more SAS expanders
not properly configured.
Amber flashing (On 250 ms Off 250 ms [five
times]; Off 1000 ms): Firmware revisions between
EMMs are different. Both EMM LEDs will blink.
Table 1-4. EMM Component Functions (continued)
Item Component Icon Function