The back of the E2800 controller includes LEDs that indicate when the controller is active, when the controller needs attention, when there is Ethernet activity, and so on.
The following example shows the LEDs on an E2800 controller with two optical (SFP+) baseboard host ports, and two optical Host Interface Card (HIC)-based host ports. These ports can be configured for 16 Gbps Fibre Channel (FC) or 10 Gbps iSCSI connections. 
The following example shows the same LEDs on an E2800 controller with two RJ-45 baseboard host ports and two RJ-45 HIC host ports. These ports provide 10 Gbps iSCSI connections. 
| 1 | Cache Active |
| 2 | Locate |
| 3 | Attention |
| 4 | Activity |
| 5 | Ethernet Status |
| 6 | Ethernet Activity |
| 7 | SAS Expansion Port Link Status |
| 8 | SAS Expansion Port Attention |
| 9 | Host Port Link Status |
| 10 | Host Port Attention |
| 11 | Host Port Link Status |
| 12 | Host Port Attention |
| LED | Status indicator | Description |
|---|---|---|
| Cache Active | Green | The cache contains data not yet written to disk. |
| Off | Either the cache is inactive or all data from the cache has been preserved in non-volatile memory. |
|
| Locate | Blue | There is an active request to physically locate the controller shelf. |
| Off | There is no active request to locate the controller shelf. |
|
| Attention | Amber | The controller is faulty and requires operator attention, and the faulty component is serviceable. |
| Off | The controller is operating normally. |
|
| Activity | Blinking green | The controller is active. |
| Ethernet Activity (right) | Green | The link between the Management port and the device to which it is connected (such as an Ethernet switch) is up. |
| Off | There is no link between the controller and the connected Ethernet port. |
|
| Blinking green | There is Ethernet activity. |
|
| Ethernet Link State (left) | Green | Link is established. |
| Off | No link is established. |
|
| SAS expansion Port Link | Green | Link is established. |
| Off | No link is established. |
|
| SAS expansion Port Link Fault | Amber | Port is degraded (one or more Phys in the port is down). |
| Off | Port is optimal (all Phys in the port are up or all Phys in the port are down since the LED is off if no cables are attached). |
|
| Host Port Link Status (SFP host port, FC or iSCSI) | Green | The link is up (Fibre Channel). If the LED is solid, the link is up, but there is no activity (iSCSI). If the LED is flashing, the link is up and there is activity (iSCSI). If the LED is off, the link is down. |
| Host Port Attention (SFP host port, FC or iSCSI) | Amber | The port requires operator attention. |
| Host Port Link Status (RJ-45 host port, iSCSI) | Green | If the LED is on, the link is established. If the LED is off, no link is established. |
| Host Port Activity (RJ-45 host port, iSCSI) | Green | If the LED is on, the link is up with no activity. If the LED is blinking, there is link activity. If the LED is off, no link is established. |
