Symptoms

Dell PowerEdge servers running iDRAC9 may log excessive SWC5008 errors referencing the front LED panel in the System Event Logs (SEL). SWC5008 events may also appear in the iDRAC9 Lifecycle Log. These errors can indicate either a firmware-recoverable soft lockup or a hardware fault affecting the front LED control panel. Description: The SWC5008 error appears as shown in Figure 1 and the examples below. Figure 1: iDRAC9 Dashboard Critical System Health Example System Event Log (SEL) Example: Unable to access Front LED Panel because of a hardware error condition. Lifecycle Log Example: SWC5008 Unable to access Front LED Panel because of a hardware error condition.

Cause

The front left LED control panel is monitored and managed by the iDRAC (BMC) controller embedded on PowerEdge servers. Regular status queries occur every five seconds to verify the presence and current health of the front LED panel. The iDRAC also maintains current installed firmware on this controller board. If there is an applicable update in the iDRAC firmware, the iDRAC attempts to push the LED firmware update during iDRAC boot cycles. In either of these sequences, the iDRAC uses an i2c circuit to communicate with the LED controller board. Timeouts in communication between the iDRAC and the Left Control Panel during these sequences lead to the SWC5008 error events logged in the SEL and Lifecycle Log. Figure 2: Front LED Panel PowerEdge R740XD The Left Control Panel (LCP) supports at-the-box management and system health at a glance. It is located on the left ear of the chassis when viewing from the front of the system. On most PowerEdge servers, the LCP is offered in two options: Quick Sync 2 buttonStatus LED 1 button In either control panel configuration, five status LED indicators provide a real-time, at-the-box indication of a hardware fault affecting the server. Figure 3 explains these indicator LEDs. Figure 3: LED Health Status Indicators PowerEdge Under normal server health conditions, these five LEDs appear off. When a hardware fault is detected on one of the subsystems aligned with these LEDs, the backlight illuminates in a solid amber state. These LEDs are controlled by the iDRAC (BMC) controller through communication on the i2c circuit. The light bars for both Quick Sync and System ID are not managed through this same i2c circuit and operate independently of the status LEDs.

Resolution

Note: Dell Technologies recommends upgrading to the latest iDRAC9 firmware to resolve this issue. Refer to iDRAC9 Versions and Release Notes for the latest iDRAC9 firmware available for your system. Available iDRAC9 firmware versions may differ by system model. iDRAC9 firmware version 4.22.00.53 introduced mechanisms to recover Front Panel LED controllers from a soft lockup condition. These changes are present in all iDRAC9 releases starting with 4.32.10.00. The changes in this release do not mask true Front LED Panel hardware failures. If errors persist after implementing this firmware, continue to troubleshoot hardware. Note: The SWC5008 error can also be caused by the front USB port status attribute being disabled in iDRAC on certain firmware versions. Before proceeding with hardware troubleshooting, refer to PowerEdge: How to recover from "SWC5008 Unable to access Front LED Panel because of a hardware error condition" to check this setting. If SWC5008 events continue after applying iDRAC9 firmware version 4.22.00.53 or later (4.32.10.00 or later) and verifying the front USB port status attribute, investigate the front LED panel for a possible hardware fault. Use the following troubleshooting steps as a starting point: Check the Front LED Control Board cable for damage.Reseat the Front LED Control Board cable to resolve connection issues.Replace the Front LED Control Board if the LED has failed.Replace the system board if the issue continues to persist.

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