Thank you for following up on this!
When looking into your issue, I didn't notice anything that would point to the older legacy Logstash plugin being stopped or deprecated. However, I reached out to the Microsoft Sentinel team so they can take a closer look into your issue and will update as soon as possible.
Links:
- Use Logstash to stream logs with HTTP Data Collection API (legacy)
- Use Logstash to stream logs with pipeline transformations via DCR-based API
- Microsoft Sentinel output plugin for Logstash
If you have any other questions, please let me know. Thank you for your time and patience throughout this issue.