First, it’s interesting to note that the Polybase engine uses “pdw_user” as its user account. That’s not a blocker here because I have an open door policy on my Hadoop cluster: no security lockdown because it’s a sandbox with no important information. Second, my IP address on the main machine is 192.168.58.1 and the name node for my Hadoop sandbox is at 192.168.58.129. These logs show that my main machine runs a getfileinfo command against /tmp/ootp/secondbasemen.csv. Then, the Polybase engine asks permission to open /tmp/ootp/secondbasemen.csv and is granted permission. Then…nothing. It waits for 20-30 seconds and tries again. After four failures, it gives up. This is why it’s taking about 90 seconds to return an error message: it tries four times.
Aside from this audit log, there was nothing interesting on the Hadoop side. The YARN logs had nothing in them, indicating that whatever request happened never made it that far.
Here’s hoping there’s a solution in the future.