I have ArcGIS Enterprise 10.7.1 with OS RHEL 7.9, planning to upgrade to 10.9.1.
As recommended at ESRI website, I started with upgrading Portal for ArcGIS which were 2 steps:
1. Running Portal for ArcGIS 10.9.1 installer silently - > succeeded.
2. Running the Portal upgrade silently -> failed.
The error message was : 'The data directory was initialized by PostgreSQL version 10, which is not compatible with this version 12.4.'
Appreciate any comment and feedback to resolve.
Thanks.