Replication is pretty straightforward if you have Kerberos already in your env:
- Setup Solr to use Kerberos authentication.
- Try to use the admin UI. You can't, with the 403 errors as seen in previously attached screenshots.
The old Admin UI works fine.
The rub here is that this requires setting up a Kerberos ticket server, etc., which really isn't the easiest thing in the world (I don't know how to do it, for example).
Lucidworks has customers who have seen this, most recently using 6.4.1, so I can confirm it still exists in the latest Solr release. Ishan's initial report was against 6.2, so it's not just the latest; IMO we can assume it's all 6.x releases, and maybe even 5.5.2 per another reporter.
There's a workaround for now - use the old UI - but if the old UI is removed, users with Kerberos auth will be unable to use the Admin UI.