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Copy /usr/local/solr/avalon to /usr/local/solr/avalon_r5
Unload and clean out Solr index: http://localhost:8983/solr/admin/cores?action=UNLOAD&core=avalon_r5&deleteIndex=true
Recreate core
Clone Matterhorn
Copy matterhorn and opencast folder to a new location.
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Manually kick off rake avalon:reindex. This can take a very long time if you have a large collection, better run it in a tmux session.