Per your documentation (hms-federation-concepts), Apache Iceberg tables in federated external Hive metastores are Public Preview on Databricks Runtime 16.2+, with no enablement steps listed. On our workspace, every read of a federated Iceberg table fails with:

[UNSUPPORTED_FEATURE.TABLE_OPERATION] The feature is not supported:
Table `browse_only_table` does not support batch scan. SQLSTATE: 0A000

while an identically-federated plain parquet table reads successfully. We believe the foreign-Iceberg-scan preview is not enabled for our account/workspace and request enablement (or the documented enablement path).

Controlled experiment (same connection, same foreign catalog, same external location, same GCS bucket, same warehouse)

Table Format Result

The failure reproduces identically on DBSQL serverless, serverless jobs, and a classic DBR 17 cluster (spark.read.table).

Everything verified on our side

• Unity Catalog classifies the tables correctly: data_source_format: ICEBERG, browse_only: false, securable kind TABLE_FOREIGN_HIVE_METASTORE_EXTERNAL
• Metadata operations all work: SHOW TABLES, DESCRIBE (columns resolve), SHOW TBLPROPERTIES (returns metadata_location), REFRESH FOREIGN TABLE
• HMS representation follows the Iceberg HiveCatalog convention: TBL_TYPE=EXTERNAL_TABLE; table params table_type=ICEBERG, metadata_location=<current>, spark.sql.sources.provider=iceberg, spark.sql.sources.schema.numParts/part.0; plain FileInputFormat/LazySimpleSerDe storage descriptor
• The metadata_location file exists and is current (verified immediately before test)
• Storage credential validation (validate-storage-credentials): READ / LIST / WRITE / DELETE / PATH_EXISTS all PASS
• Privileges granted: ALL PRIVILEGES, MANAGE, READ FILES, CREATE FOREIGN SECURABLE, CREATE MANAGED STORAGE (external location); ALL PRIVILEGES + MANAGE (catalog); querying principals include the catalog owner
• Foreign catalog recreated multiple times, including with storage_root set at creation; authorized_paths covers the table path
• External location fallback mode tested both ways
• read_files('gs://…') on the same paths returns the data (storage plane fully authorized)
• Independent client proof: pyiceberg, connecting through a thrift HMS service backed by the same metastore database, lists the namespaces/tables, resolves metadata_location, and reads the rows successfully — the same resolution chain federation uses
• The table object consistently shows storage_location: None; PATCH via update_mask=storage_location is rejected for foreign securables (appears to be crawler-managed)