Determine MaxEventStoreDays setting in /etc/cb/cb.conf as a starting point to purge
grep MaxEventStoreDays /etc/cb/cb.conf
Determine the cbevent shards (ProcSolrShards) that are present on the local server
Run the following command, replacing XX with MaxEventStoreDays and SHARD with any shards that are present on the local server. If additional space needs to be recovered, reduce this purge time. This query selects all data older than XX days and deletes it. This command may take a while to complete. Solr will return a response when the purge is done
curl http://127.0.0.1:8080/solr/SHARD/update?commit=true -H "Content-Type: text/xml" -d "<delete><query>last_server_update:[* TO NOW-XXDAYS]</query></delete>"
Please open a support case if Solr is taking over an hour to return