I have upgraded nexus repository from 2.x to 3.x through following path:
2.4.14 -> 3.4.0 -> 3.5.1
All nexus services were packed in docker with data directory mapped from host's. For all services I use default either sonatype/nexus or sonatype/nexus3 containers. Nexus web interface is hidden behind nginx with simple reverse proxying.
I use the nexus service with boot-cj (with no credentials) tools which manages dependencies the same way as maven. Anyway the tool first downloads nexus-maven.xml with relevant sha1 files and tries to download jars. It works fine with all 2.x I had.
I created a proxy repository against remote sonatype-snapshots repo. When I start compilation I have Could not find artifact error. I found that the meatdata files are cached but all poms and jars.
I have tried to fix it by cleaning cache with the clean_cache file trick and more rough rm -rfv /srv/nexus3/nexus-data/cache/* with no success. There are no any logs about error. Also I have checked manually that required artefact exists in the remote repository. More obvious Rebuild index button gave no solution. I do not thing it is a problem with nginx, but who knows? Also leaving overnight to run the scheduled tasks did not help.
The expected artifact is org.eclipse.rdf4j:rdf4j:pom:2.3-20170901.145510-11.