On Aug 21, 2007, at 8:14 PM, ChaoChun Liang wrote:
the stderr under the map-log shows the message, "Hadoop Pipes Exception: Illegal text protocol command"
Oh dear. Please file a bug on this. Which version of Hadoop are you running? In particular, are you running with or without HADOOP-1553? Do you have mapred.userlog.limit.kb set to 0 or non-0?
The C++ library has two modes the binary and text protocols. It should always use the binary protocol, which it detects by having a environment variable hadoop.pipes.command.port or hadoop.pipes.command.file defined. Since you clearly had the text protocol running, the environment must have been messed up somehow. The text protocol is really there to help me in debugging the framework, although it means that if you run a pipes program from the console you can interact with it.
3. Any guide line for *pipe*(ex. how to configure, how it works?)
I plan on allocating time in the next couple weeks to write up some of how to use and configure pipes. There is a little bit on how to run the pipes program stand-alone for debugging at the bottom of the page:
http://wiki.apache.org/lucene-hadoop/HowToDebugMapReducePrograms -- Owen
