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Manoj Govindassamy commented on HDFS-12357: ------------------------------------------- [~yzhangal], Here is one other jira on the similar lines - HDFS-12203 - INodeAttributesProvider#getAttributes() support for default/passthrough mode. > Let NameNode to bypass external attribute provider for special user > ------------------------------------------------------------------- > > Key: HDFS-12357 > URL: https://issues.apache.org/jira/browse/HDFS-12357 > Project: Hadoop HDFS > Issue Type: Bug > Reporter: Yongjun Zhang > Assignee: Yongjun Zhang > Attachments: HDFS-12357.001.patch > > > This is a third proposal to solve the problem described in HDFS-12202. > The problem is, when we do distcp from one cluster to another (or within the > same cluster), in addition to copying file data, we copy the metadata from > source to target. If external attribute provider is enabled, the metadata may > be read from the provider, thus provider data read from source may be saved > to target HDFS. > We want to avoid saving metadata from external provider to HDFS, so we want > to bypass external provider when doing the distcp (or hadoop fs -cp) > operation. > Two alternative approaches were proposed earlier, one in HDFS-12202, the > other in HDFS-12294. The proposal here is the third one. > The idea is, we introduce a new config, that specifies a special user (or a > list of users), and let NN bypass external provider when the current user is > a special user. > If we run applications as the special user that need data from external > attribute provider, then it won't work. So the constraint on this approach > is, the special users here should not run applications that need data from > external provider. > Thanks [~asuresh] for proposing this idea and [~chris.douglas], [~daryn], > [~manojg] for the discussions in the other jiras. > I'm creating this one to discuss further. -- 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