Hi, I am migrating several million records from an existing vtls system to koha. We are using mariadb, koha 17.05 (have pulled from master yesterday ), elastic search 5.4 and plack on debian systems. As I wanted to preserve all the authority to biblio record links I wrote my own migration script based on the relevant koha source. Searching in the koha authorities intra will find the authority record but usually lists the number of biblio records having the auth as zero, but not always. If I check the biblio index in ES the items have the correct auth id in the "an" field. I can find no difference between the biblio records in the ES index that are reported as linked to the auth record to the ones that are not. I connect the biblio recs to the authorities in the marc21 structure by putting the koha auth id in field 100 sub field 9 (if it is a name auth). These marc records are now in the new biblio_metadata table. How does koha find the biblio records connected to a paticular auth record ? Is this done dynamically by searching the ES indexes ? Is this an issue with the zebra database? Is it still required ? I haven't been loading data into it since we switched to ES. Best Regards, Dave