Rear panel LEDs 65
1
See the qualified HD mini-SAS host cable options described in the QuickSpecs.
2
When port is down, both LEDs are off.
Figure 30 LEDs: MSA 1050 controller module (SFF-8644 12 Gb SAS connectors)
NOTE: Once a Link Status LED is lit, it remains so, even if the controller is shutdown via the SMU or CLI.
When a controller is shutdown or otherwise rendered inactive—its Link Status LED remains illuminated—falsely 
indicating that the controller can communicate with the host. Though a link exists between the host and the chip on the 
controller, the controller is not communicating with the chip. To reset the LED, the controller must be properly 
power-cycled [see “Powering on/powering off” (page 21)].
LED Description Definition
1 Host SAS
1
Link Status
Off — No link detected.
Green — The port is connected and the link is up.
2 Host SAS
1
Link Activity
Off — The link is idle.
Blinking green — The link has I/O activity.
3 Network Port Link 
Active Status
2
Off — The Ethernet link is not established, or the link is down.
Green — The Ethernet link is up (applies to all negotiated link speeds).
4 Network Port Link Speed
2
Off — Link is up at 10/100base-T negotiated speeds.
Amber — Link is up and negotiated at 1000base-T.
5 OK to Remove Off — The controller module is not prepared for removal.
Blue — The controller module is prepared for removal.
6 Unit Locator Off — Normal operation.
Blinking white — Physically identifies the controller module.
7 FRU OK Off — Controller module is not OK.
Blinking green — System is booting.
Green — Controller module is operating normally.
8 Fault/Service Required Amber — A fault has been detected or a service action is required.
Blinking amber — Hardware-controlled power-up or a cache flush or restore error.
9 Cache Status Green — Cache contains unwritten data and operation is normal. The unwritten 
information can be log or debug data that remains in the cache, so a Green cache status 
LED does not, by itself, indicate that any user data is at risk or that any action is necessary.
Off — In a working controller, cache is clean (contains no unwritten data).
This is an occasional condition that occurs while the system is booting.
Blinking green — A CompactFlash flush or cache self-refresh is in progress, indicating 
cache activity. 
See also Cache Status LED details.
10 Expansion Port Status Off — The port is empty or the link is down.
On — The port is connected and the link is up.