If the following error shows up when you are trying to create a solr core:
Unable to create core [tweets_shard1_replica1] Caused by: XML document structures must start and end within the same entity.
How do you get past this issue?
You must verify that the solrconfig.xml has valid XML format and isn't missing entities.
You can use this website to validate the XML : XML Validator
You can also get a fresh copy of the solrconfig file from github if you have modified the original and don't have a backup.
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