Data Domain: Troubleshooting Memory Errors

Summary: This article describes how to troubleshoot memory-related alerts on Dell Data Domain systems, including how to identify a faulty DIMM that requires replacement. It covers common alert codes, root causes of correctable and uncorrectable ECC errors, and step-by-step resolution guidance such as initiating POST-Package Repair (PPR), running diagnostic CLI commands, and performing physical troubleshooting. ...

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Symptoms

  • DDOS generates memory-related alerts, including:
    • DIMM-00001: Correctable ECC logging limit reached
    • DIMM-00002: Multibit uncorrectable ECC error
    • DIMM-00003: Memory card failure
    • ENVIRONMENT-00009: Correctable ECC errors exceed threshold
    • ENVIRONMENT-00013: Uncorrectable ECC error detected
    • ENVIRONMENT-00044: Memory riser fault detected
    • MEM-00001: DIMM failure detected; DDFS will not start
    • MEM-00002: Memory size below configured value
  • iDRAC System Event Log (SEL) reports
    • MEM0802: The memory health monitor feature has detected a degradation in the DIMM installed in DIMM [slot number]. Reboot system to initiate self-heal process.
  • System reboots triggered by uncorrectable memory errors
  • DDFS does not start or cannot be enabled
  • System enters a down state due to memory hardware failure
  • Other alerts may mask memory issues (for example, CPU Machine Check Error)

Cause

  • Data Domain DIMMs use Error Correcting Code (ECC) to detect and correct memory errors.
  • Correctable errors accumulate and trigger alerts when thresholds are exceeded.
  • Uncorrectable errors indicate a hardware fault and may cause system instability or reboot.
  • Failure of a DIMM or memory riser reduces available memory and may prevent DDFS from starting.
🛠️ NOTE: Other symptoms or alerts may mask memory errors - for example, CPU Machine Check Error - a reboot may address the underlying memory issue and deeper log analysis or troubleshooting may be required.

Resolution

✅ NOTE: If an DIMM error is reported on Dell PowerEdge based systems, the first action to recover is to reboot the DataDomain unit. This will initiate PPR (POST Package Repair) to recover the DIMM.

DIMM Alert - Reboot Decision Guide

 The BIOS Post Package Repair (PPR) feature can repair affected memory cells during a reboot.

Reboot decision guidance:

Scenario Recommendation
Alert just appeared; system stable; production backups running Schedule a maintenance window within 24–48 hours to reboot the system
Alert present for multiple days without action Schedule a reboot as soon as possible to avoid escalation to uncorrectable error (MEM0001)
System idle or in maintenance window Reboot immediately to allow PPR self-heal

Critical warnings:

  • Do not remove or swap the DIMM before rebooting. PPR requires the original DIMM in place.
  • The system may reboot automatically more than once during self-heal. This is expected behavior.
  • If self-heal succeeds, DIMM replacement is not required.
  • If the alert persists after reboot or escalates to MEM0001, contact Dell Support.

Standard Troubleshooting and Resolution Steps

  1. Reboot the Data Domain system (PowerEdge platforms) to initiate PPR.
  2. Identify the faulty component (DIMM, CPU, or motherboard) using alerts and diagnostics.
  3. Compare the current system state with a previous AutoSupport snapshot (before the alert).
  4. Run the following DD CLI commands: 
    alerts show current
system show meminfo
enclosure show memory
log view debug/messages.engineering
  5. Run DDOS Hardware Healthcheck to confirm the hardware fault.
  6. Perform physical checks:
    • Reseat the DIMM securely
    • Swap with a known good DIMM for isolation testing
  7. Replace the faulty component based on diagnostic results.
  8. If the system does not boot:
    • Remove non-essential hardware
    • Boot with a minimal configuration (single DIMM in slot 0)
  9. Collect a Support Bundle and open a Service Request if required.

Additional Information

References:

Affected Products

Data Domain, PowerProtect Data Protection Appliance, Data Domain, Data Domain Deduplication Storage Systems, PowerProtect Data Protection Hardware
Article Properties
Article Number: 000034334
Article Type: Solution
Last Modified: 01 Jul 2026
Version:  10
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