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Konstantin Shvachko commented on HDFS-14017: -------------------------------------------- Checked v002 patch. # Main question if we could simplify this by assuming that the first address in the list of configured NNs corresponds to the Active? I don't think we should do the discovery of Active for IPFailover. Suppose that by mistake somebody transitions a wrong NN to active. It will be discovered by ORPP and the cluster will start fine, but then it wont failover correctly when needed. # Not sure why changes in {{ConfiguredFailoverProxyProvider}}. We must use {{addressKey}} in getProxyAddresses() instead of {{HdfsClientConfigKeys.DFS_NAMENODE_RPC_ADDRESS_KEY}}. Otherwise it breaks {{InMemoryAliasMapFailoverProxyProvider}}. # Should not import {{SecurityUtil.*}}. > ObserverReadProxyProviderWithIPFailover should work with HA configuration > ------------------------------------------------------------------------- > > Key: HDFS-14017 > URL: https://issues.apache.org/jira/browse/HDFS-14017 > Project: Hadoop HDFS > Issue Type: Sub-task > Reporter: Chen Liang > Assignee: Chen Liang > Priority: Major > Attachments: HDFS-14017-HDFS-12943.001.patch, > HDFS-14017-HDFS-12943.002.patch, HDFS-14017-HDFS-12943.003.patch > > > Currently {{ObserverReadProxyProviderWithIPFailover}} extends > {{ObserverReadProxyProvider}}, and the only difference is changing the proxy > factory to use {{IPFailoverProxyProvider}}. However this is not enough > because when calling constructor of {{ObserverReadProxyProvider}} in > super(...), the follow line: > {code:java} > nameNodeProxies = getProxyAddresses(uri, > HdfsClientConfigKeys.DFS_NAMENODE_RPC_ADDRESS_KEY); > {code} > will try to resolve the all configured NN addresses to do configured > failover. But in the case of IPFailover, this does not really apply. > > A second issue closely related is about delegation token. For example, in > current IPFailover setup, say we have a virtual host nn.xyz.com, which points > to either of two physical nodes nn1.xyz.com or nn2.xyz.com. In current HDFS, > there is always only one DT being exchanged, which has hostname nn.xyz.com. > Server only issues this DT, and client only knows the host nn.xyz.com, so all > is good. But in Observer read, even with IPFailover, the client will no > longer contacting nn.xyz.com, but will actively reaching to nn1.xyz.com and > nn2.xyz.com. During this process, current code will look for DT associated > with hostname nn1.xyz.com or nn2.xyz.com, which is different from the DT > given by NN. causing Token authentication to fail. This happens in > {{AbstractDelegationTokenSelector#selectToken}}. New IPFailover proxy > provider will need to resolve this as well. -- 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