This took me a while to discover what the issue was, so to save others time I include the following details.
If you have an HDFS storage plugin configured and execute a SHOW SCHEMAS query then you would expect to get something like like this: sqlline -u jdbc:drill:sk=zen-drill-vm 0: jdbc:drill:sk=zen-drill-vm> show schemas; +---------------------+ | SCHEMA_NAME | +---------------------+ | INFORMATION_SCHEMA | | dfs.default | | dfs.root | | dfs.tmp | | hdfs.default | | hdfs.pm | | hdfs.root | | hdfs.zen | | sys | +---------------------+ 9 rows selected (0.328 seconds) 0: jdbc:drill:sk=zen-drill-vm> If the HDFS services are not running then you will get this: 0: jdbc:drill:sk=zen-drill-vm> show schemas; Error: SYSTEM ERROR: ConnectException: Connection refused [Error Id: 724d9d26-8798-4165-b266-fb139a23145c on smech-vm-hdt01:31010] (state=,code=0) 0: jdbc:drill:sk=zen-drill-vm> As you can see there is no hint as to what the problem is apart from the hostname and port number 31010, which after a while a realised was the port used by drill to access the HDFS service. I initially thought it was a problem with the web interfaces or the sqlline utility trying to connect to drill, since the drill node is the same as the HDFS node; maybe the solution to the problem would have been more obvious to me if I had drill and HDFS installed on different nodes. Perhaps this error could be trapped, and either ignore the HDFS schemas or maybe display a warning message of some kind. This behaviour may also occur for other storage plugins such as HIVE but I do not know. Should I raised this as a Jira for this ? Cheers — Chris
