[ http://issues.apache.org/jira/browse/HADOOP-466?page=comments#action_12430576 ] Yoram Arnon commented on HADOOP-466: ------------------------------------
if HADOOP_IDENT_STRING isn't specified explicitly, it defaults to $USER. pid files that incorporate HADOOP_IDENT_STRING will then have different names when invoked by different users, negating their effect as uniquely identifying a process using that conf dir. slaves bind to the configured port, but if that fails they scan forward up to 10 ports to find a port to bind, so they'll start just fine, connect the the same master and presto, we have two slaves on the same machine running as different users. I always use the --config parameter, so yes, I'm not overly concerned, but I've seen this happen. It's not a big deal, but as long as you're going to the trouble of hashing the conf dir into the file names, I thought it might be another improvement. > Startup scripts will not start instances of Hadoop daemons w/different > configs w/o setting separate PID directories > ------------------------------------------------------------------------------------------------------------------- > > Key: HADOOP-466 > URL: http://issues.apache.org/jira/browse/HADOOP-466 > Project: Hadoop > Issue Type: Improvement > Affects Versions: 0.5.0 > Reporter: Vetle Roeim > Fix For: 0.6.0 > > Attachments: hadoop-466.diff > > > Configuration directories can be specified by either setting HADOOP_CONF_DIR > or using the --config command line option. However, the hadoop-daemon.sh > script will not start the daemons unless the PID directory is separate for > each configuration. > The issue is that the code for generating PID filenames is not dependent on > the configuration directory. While the PID directory can be changed in > hadoop-env.sh, it seems a little unnecessary to have this restriction. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira
