Troubleshooting PI Web API Crawler Indexing Issues in PI Vision

title: "Troubleshooting PI Web API Crawler Indexing Issues in PI Vision" excerpt: "Explore strategies to address discrepancies in PI Web API crawler indexing, affecting PI Vision tag visibility." categories: ["PI System", "Data Management"] tags: ["PI Web API", "PI Vision", "Tag Indexing", "Troubleshooting"]

Understanding PI Web API Crawler Indexing Issues

In a well-architected PI System environment, the consistency of tag visibility across different platforms like PI Vision is crucial. A common issue arises when the PI Web API crawler fails to index all the available PI tags, leading to missing tag data in PI Vision. Understanding and resolving this discrepancy requires a methodical approach, focusing on the service account, security settings, and tag parameters.

The Problem

In one such case, a PI Web API crawler was found to be indexing only 40,805 tags from the archive, whereas PI SMT reported 42,447 data streams. Despite running every three minutes, the crawler left over 1,600 tags unindexed. Further analysis via direct PI Web API queries showed a count of 42,444, indicating only a three-tag difference, which points towards potential indexing issues due to tag parameters.

Investigative Steps

1. Service Account Verification:

   • Identify the service account running the PI Web API Crawler.
   • Verify the PI Identity of this service account to ensure it aligns with necessary access levels.

2. Security Settings Analysis:

   • Examine the security settings for the unindexed PI Points. Check if the connected identity is part of the piadmins group, which typically should prevent access issues.

3. Tag Parameter Check:

   • Tags might have specific parameters that restrict them from being indexed. Investigating attributes like point type, security settings, and archive availability could uncover potential barriers.

4. PI Vision Launch Analysis:

   • Attempt to access PI Vision using the service account itself. If tags become visible, the problem likely resides in the specific user account permissions rather than the service account.

5. User Account Permissions:

   • If tags are visible with the service account but not the user account, reassess the permissions of the user account to ensure they mirror those that grant tag visibility.

Conclusion

Indexing discrepancies in PI Web API not only affect data accessibility but also disrupt operational efficiency in using PI Vision. Identifying the root cause involves careful examination of tag parameters, role-based security assessments, and ensuring that the PI Web API crawler configuration aligns with the intended permissions. By following these diagnostic steps, one can minimize visibility issues and maintain data integrity across PI System applications.

These strategies should not only resolve existing discrepancies but also guide preventive measures for future indexing challenges.