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Lars Francke commented on HDFS-11242: ------------------------------------- [~hexiaoqiao] I don't understand. Can you be more specific? The usecase I see is simple: You add new nodes but forget to specify the proper rack, the only way to fix it now is to restart the NameNodes which is not a good experience. I haven't looked at the patch in detail but all I need is a way to call reloadCachedMappings on the DNSToSwitchMapping. We can change the ScriptBasedMapping to not extend CachedDNSToSwitchMapping or to change CachedDNSToSwitchMapping to periodically invalidate all entries or something like that. > Add refresh cluster network topology operation to dfs admin > ----------------------------------------------------------- > > Key: HDFS-11242 > URL: https://issues.apache.org/jira/browse/HDFS-11242 > Project: Hadoop HDFS > Issue Type: Improvement > Components: namenode > Affects Versions: 3.0.0-alpha1 > Reporter: Reid Chan > Priority: Minor > Attachments: HDFS-11242.002.patch, HDFS-11242.patch > > > The network topology and dns to switch mapping are initialized at the start > of the namenode. > If admin wants to change the topology because of new datanodes added, he has > to stop and restart namenode(s), otherwise those new added datanodes are > squeezed under /default-rack. > It is a low frequency operation, but it should be operated appropriately, so > dfs admin should take the responsibility. -- This message was sent by Atlassian JIRA (v7.6.3#76005) --------------------------------------------------------------------- To unsubscribe, e-mail: hdfs-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: hdfs-issues-h...@hadoop.apache.org