Hi George, Actually, in my hdfs-site.xml, I always set 'dfs.replication'to 2. But still encounter this issue.
Thanks! 2013/6/21 George Kousiouris <[email protected]> > > Hi, > > I think i have faced this before, the problem is that you have the rep > factor=3 so it seems to hang because it needs 3 nodes to achieve the factor > (replicas are not created on the same node). If you set the replication > factor=2 i think you will not have this issue. So in general you must make > sure that the rep factor is <= to the available datanodes. > > BR, > George > > > On 6/21/2013 12:29 PM, sam liu wrote: > > Hi, > > I encountered an issue which hangs the decommission operatoin. Its steps: > 1. Install a Hadoop 1.1.1 cluster, with 2 datanodes: dn1 and dn2. And, > in hdfs-site.xml, set the 'dfs.replication' to 2 > 2. Add node dn3 into the cluster as a new datanode, and did not change > the 'dfs.replication' value in hdfs-site.xml and keep it as 2 > note: step 2 passed > 3. Decommission dn3 from the cluster > > Expected result: dn3 could be decommissioned successfully > > Actual result: decommission progress hangs and the status always be > 'Waiting DataNode status: Decommissioned' > > However, if the initial cluster includes >= 3 datanodes, this issue > won't be encountered when add/remove another datanode. > > Also, after step 2, I noticed that some block's expected replicas is 3, > but the 'dfs.replication' value in hdfs-site.xml is always 2! > > Could anyone pls help provide some triages? > > Thanks in advance! > > > > -- > --------------------------- > > George Kousiouris, PhD > Electrical and Computer Engineer > Division of Communications, > Electronics and Information Engineering > School of Electrical and Computer Engineering > Tel: +30 210 772 2546 > Mobile: +30 6939354121 > Fax: +30 210 772 2569 > Email: [email protected] > Site: http://users.ntua.gr/gkousiou/ > > National Technical University of Athens > 9 Heroon Polytechniou str., 157 73 Zografou, Athens, Greece > >
