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Yongjun Zhang commented on HDFS-11799: -------------------------------------- Hi [~brahmareddy], Thanks for working on this and sorry for the delayed review. Some comments: 1. Suggest to add some comments about dtpReplaceDatanodeOnFailureReplication when it was introduced. And add a default config with description in hdfs-default.xml 2. about the following code {code} final int d; try { d = findNewDatanode(original); } catch (IOException ioe) { if (dfsClient.dtpReplaceDatanodeOnFailureReplication > 0 && nodes.length >= dfsClient.dtpReplaceDatanodeOnFailureReplication) { DFSClient.LOG.warn( "Failed to add a new datanode for write pipeline, minimum block replication:" + dfsClient.dtpReplaceDatanodeOnFailureReplication + ", good datanode size: " + nodes.length); return; } throw ioe; } {code} 2.1 add comment explaining things 2.2 add the ioe to the warn, so to expose the ioe in the log 3. Any chance to have a unit test? Thanks. > Introduce a config to allow setting up write pipeline with fewer nodes than > replication factor > ---------------------------------------------------------------------------------------------- > > Key: HDFS-11799 > URL: https://issues.apache.org/jira/browse/HDFS-11799 > Project: Hadoop HDFS > Issue Type: Bug > Reporter: Yongjun Zhang > Attachments: HDFS-11799.patch > > > During pipeline recovery, if not enough DNs can be found, if > dfs.client.block.write.replace-datanode-on-failure.best-effort > is enabled, we let the pipeline to continue, even if there is a single DN. > Similarly, when we create the write pipeline initially, if for some reason we > can't find enough DNs, we can have a similar config to enable writing with a > single DN. > More study will be done. > -- This message was sent by Atlassian JIRA (v6.4.14#64029) --------------------------------------------------------------------- To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org