Error Reference

Discovery pattern failed: pattern did not match target device

Discovery pattern failed: pattern did not match target device

Where this appears

This error appears in the Discovery Status under Discovery > Status > Discovery Status, in ECC Queue records, and in Discovery logs when a Discovery or Service Mapping pattern cannot successfully identify or classify a target CI. The error occurs during scheduled discovery jobs or manual discovery operations when pattern matching logic fails.

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Overview
Tasks
CMDB
API
Metrics
Monitor
Internals
Instance:sourdoughdev·Version:Yokohama
Instance StateONLINE
System StatusFully Operational
Session Timeout90 minutes
Logged-In Sessions2 (20 active)
Build Nameyokohama-12-18-2024_p1
IP Address10.159.128.43
Instance HealthHealth Score: 90%
🔥 5dSourdough (Chrome Plugin)Dark Mode

Cause

Pattern identification criteria are too restrictive or contain incorrect values that don't match the actual data returned from the target device by probes. (high likelihood)

Required probes failed to execute successfully or returned incomplete data, preventing the pattern from gathering necessary information for matching. (high likelihood)

Target device configuration has changed since the pattern was created, causing previously working identification logic to no longer match current device state. (medium likelihood)

Pattern dependency issues where prerequisite patterns or shared libraries are missing, outdated, or contain errors that prevent proper execution. (medium likelihood)

Network connectivity issues, credential problems, or insufficient permissions preventing probes from collecting complete device information required for pattern matching. (low likelihood)

Fix

Step 1: Navigate to Discovery > Status > Discovery Status and locate the failed discovery job to identify the specific pattern name and target device details.

Step 2: Check the ECC Queue at System Diagnostics > ECC Queue for related probe execution records and examine any error messages or incomplete probe results.

Step 3: Open the failing pattern in Discovery > Patterns and review the Identification section to understand what criteria the pattern uses to match target devices.

Step 4: Use Discovery > Tools > Pattern Designer Test Mode or run the pattern manually against the target device to see actual probe results versus expected identification values.

Step 5: Compare the probe output data with the pattern's identification conditions, looking for mismatched values, missing data fields, or overly restrictive criteria.

Step 6: Modify the pattern identification logic to match the actual device data, or fix any probe execution issues that are preventing complete data collection.

Step 7: Test the updated pattern using Pattern Designer or re-run discovery on a single device to verify the pattern now successfully matches and identifies the target.

Step 8: Re-execute the full discovery job and monitor Discovery Status to confirm the pattern failure is resolved for all affected devices.

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