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I’m working on updating the crowd-embedded packages to version 6.0.0-EAP01 (ref , and I’m encountering an issue I where I need some guidance.
When I previously tried installing with crowd 6.0.0-rc2 I got a similar issue also with net.sh.echache. I was then unable to find any reference to the package net.sf.ehcache:ehcache-parent browsing in https://packages.atlassian.com/mvn/maven-atlassian-external/.
Error output installing crowd-core:6.0.0-rc2:

Failed to collect dependencies at com.atlassian.crowd:embedded-crowd-core:jar:6.0.0-rc2 -> com.atlassian.crowd:crowd-core:jar:6.0.0-rc2 -> net.sf.ehcache:ehcache:jar:2.10.10-atlassian-2: Failed to read artifact descriptor for net.sf.ehcache:ehcache:jar:2.10.10-atlassian-2: The following artifacts could not be resolved: net.sf.ehcache:ehcache-parent:pom:3.1

When running mvn install it fails installing net.sf.ehcache (see below). I cannot seem to find net.sf.ehcache/2.10.10.20.11 anywhere in maven-atlassian-external when browsing manually either, but after a while I discovered them in maven central: https://mvnrepository.com/artifact/net.sf.ehcache/ehcache?repo=terracotta.
Error output with crowd-core:6.0.0-EAP01:

Could not resolve dependencies for project ...: The following artifacts could not be resolved: net.sf.ehcache:ehcache:jar:2.10.10.20.11 (absent): Could not find artifact net.sf.ehcache:ehcache:jar:2.10.10.20.11

Any advice on how to proceed would be appreciated. I see that the link to the package I found n maven central is actually broken: https://repo.terracotta.org/maven2/net/sf/ehcache/ehcache/2.10.10.20.11

Edit#1: I’m trying a workaround by manually downloading the jar and pom files which are available on central and manually installing them into my local .m2 and running an offline install

Edit#2: Deeper down the rabbit hole I’ve now manually installed ehcache and ehcache-root using mvn install:install-file. The remaining snag now is ehcache-root with a reference to ehcache-parent version 3.2, which apparently doesn’t exist online, but only points to a 404. I really wonder what’s the meaning of this. Does Atlassian have an internal fork with this package that’s offline?

Edit#3: Following up this one. I was able to fix the install of crowd-core by overriding the strange ehcache version in dependencyManagement, selecting a version that’s available on maven central:

<dependencyManagement>
      <dependency>
        <groupId>net.sf.ehcache</groupId>
        <artifactId>ehcache</artifactId>
        <version>2.10.9.2</version>
      </dependency>
</dependencyManagement>