FAST ESP Error: Document summary too short, couldn't unpack

The FAST ESP error, Document summary too short, couldn't unpack, occasionally occurs after performing an index profile update. In the past, my solution to this problem involved executing a manual cold update. While this works every time, it does require that you refeed all of your content. Definitely not the ideal solution when dealing with a production system.

I discovered a TechNet posting this morning that offers another solution that's not destructive. The following are the steps described in the post:

  1. Stop the QR Server (nctrl stop qrserver).
  2. Delete the %FASTSEARCH%\var\qrserver\webcluster\15100\cache_cs directory.
  3. Start the QR Server (nctrl start qrserver).
  4. Stop Search (nctrl stop search-1).
  5. Delete the %FASTSEARCH%\var\searchctrl directory.
  6. Start Search (nctrl start search-1)
  7. Repeat the above steps on any systems in the cluster running a QR Server or Search component.

A big thanks to Rob Va for the solution!