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Home > Success Center > Network Configuration Manager (NCM) > NCM is not detecting any changes on device configs

NCM is not detecting any changes on device configs

Updated March 27, 2017


One of NCMs key features is to detect changes between two configs from the same device and flag for review.

At times, although real differences, there are minor changes that are relevant that are detected and flagged. In some situations, differences are altogether ignored and nothing is flagged. 



All NCM versions



  1. A comparison criteria was introduced to NCM that makes NCM ignore everything.
  2. NCM_CacheDiffResults table and NCM_ComparisonCache in the NCM database have grown out of sync and is so large the difftool does not work properly.



  1. View custom comparison Criteria and disable them one by one until you see what's causing the issue.
    1. Go to Settings > NCM Settings > Comparison Criteria.
    2. When setting a Criteria to ignore, it is good practice to not only verify the Expression is ignoring the intended line, but also not ignoring anything else.
  2. Use the default Database and Archive Maintenance Job.
    1. Go to My Dashboard > Configs > Jobs.
    2. In the Add Job Specific details for Purge config cache data older than, set a timeframe where you need to run a Config Change report for or select the graphs on the Config Summary page o view.

           Note: storing unneeded data may result in performance issues.



Last modified
20:57, 26 Mar 2017