On Aug 6, 2010, at 8:35 AM, He Chen wrote: > Way#3 > > 1) bring up all 8 dn and the nn > 2) retire one of your 4 nodes: > kill the datanode process > hadoop dfsadmin -refreshNodes (this should be done on nn)
No need to refresh nodes. It only re-reads the dfs.hosts.* files. > 3) do 2) extra three times Depending upon what the bandwidth param is, this should theoretically take a significantly longer time. Since you need for the grid to get back to healthy before each kill.
