You are viewing a plain text version of this content. The canonical link for it is here.

Posted to common-commits@hadoop.apache.org by Apache Wiki <wi...@apache.org> on 2010/05/16 22:28:10 UTC

[Hadoop Wiki] Update of "Hbase/FAQ" by JeffHammerbacher

Dear Wiki user,

You have subscribed to a wiki page or wiki category on "Hadoop Wiki" for change notification.

The "Hbase/FAQ" page has been changed by JeffHammerbacher.
http://wiki.apache.org/hadoop/Hbase/FAQ?action=diff&rev1=60&rev2=61

--------------------------------------------------

   1. [[#10|Any other troubleshooting pointers for me?]]
   1. [[#20|Are there any schema design examples?]]
   1. [[#21|How do I add/remove a node?]]
+  1. [[#22|Why do servers have start codes?]]
  
  == Answers ==
  
@@ -219, +220 @@

  
  For Hadoop, use the same kind of script (starts with hadoop-*), their process names (datanode, tasktracker), and edit the slaves file. Removing datanodes is tricky, please review the dfsadmin command before doing it.
  
+ '''22. <<Anchor(22)>> Why do servers have start codes?'''
+ 
+ If a region server crashes and recovers, it cannot be given work until its lease times out. If the lease is identified only by an IP address and port number, then that server can't do any progress until the lease times out. A start code is added so that the restarted server can begin doing work immediately upon recovery. For more, see https://issues.apache.org/jira/browse/HBASE-1156.
+