Sometimes a client notices SNAPSHOT errors in the solr.log file.
solr.log:71461:2022-02-08 05:11:07.690 ERROR (qtp2619171-139584) [ ] o.a.s.c.SolrCore org.apache.solr.common.SolrException: Unsupported operation: CREATESNAPSHOT
solr.log:71494:2022-02-08 05:11:47.801 ERROR (qtp2619171-140830) [ ] o.a.s.c.SolrCore org.apache.solr.common.SolrException: Unsupported operation: DELETESNAPSHOT
These messages are sometimes generated during the Backup process. If your backups are succeeding, you may ignore the messages. If backups are failing, see Why do Backups fail?