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Jing Zhao commented on HDFS-6100: --------------------------------- +1 for the latest patch. > DataNodeWebHdfsMethods does not failover in HA mode > --------------------------------------------------- > > Key: HDFS-6100 > URL: https://issues.apache.org/jira/browse/HDFS-6100 > Project: Hadoop HDFS > Issue Type: Bug > Components: ha > Affects Versions: 2.4.0 > Reporter: Arpit Gupta > Assignee: Haohui Mai > Attachments: HDFS-6100.000.patch, HDFS-6100.001.patch > > > In {{DataNodeWebHdfsMethods}}, the code creates a {{DFSClient}} to connect to > the NN, so that it can access the files in the cluster. > {{DataNodeWebHdfsMethods}} relies on the address passed in the URL to locate > the NN. This implementation has two problems: > # The {{DFSClient}} only knows about the current active NN, thus it does not > support failover. > # The delegation token is based on the active NN, therefore the {{DFSClient}} > will fail to authenticate of the standby NN in secure HA setup. > Currently the parameter {{namenoderpcaddress}} in the URL stores the host-ip > pair that corresponds to the active NN. To fix this bug, this jira proposes > to store the name service id in the parameter in HA setup (yet the parameter > stays the same in non-HA setup). -- This message was sent by Atlassian JIRA (v6.2#6252)