[
https://issues.apache.org/jira/browse/HDFS-13469?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16444437#comment-16444437
]
Chris Douglas commented on HDFS-13469:
--------------------------------------
{quote}
It's really as simple as: the path /.reserved/.inodes/123 will access inode
123 which may really be /user/daryn/dir/mystuff. The nfs implementation relies
on inode paths.
HDFS-7878 cannot solve the problem because its an abstraction for a different
purpose.
{quote}
Agreed, but HDFS-7878 is implemented using the inode path. If the router
doesn't encode the namespace in the INodeID, then it could be a payload in a
{{PathHandle}}. Right now, that covers only one case for the inode path i.e.,
{{open}}. [~elgoiri] likely raised it because we could add handling for other
operations. That might recommend moving the logic from the client to the NN.
The router could remap the INodeIDs to encode the namespace, but if the
namespace is rebalanced, then INodeIDs could become invalid even when the
destination still "exists". Clients' interpretation of the error as a deleted
file would be incompatible. The router would need to partition the INodeID
space among all the NNs. If a client persists an INodeID and expects it to
remain valid- because that works for a single NN- that partitioning would need
to account for every NN that had ever registered with the router. This might
still be the better approach, since it has a much lower implementation cost and
covers more cases, but it has tradeoffs.
bq. For now, it might be good to throw an unsupported exception if we get
accesses to an inode path.
+1
> RBF: Support InodeID in the Router
> ----------------------------------
>
> Key: HDFS-13469
> URL: https://issues.apache.org/jira/browse/HDFS-13469
> Project: Hadoop HDFS
> Issue Type: Sub-task
> Reporter: Íñigo Goiri
> Priority: Major
>
> The Namenode supports identifying files through inode identifiers.
> Currently the Router does not handle this properly, we need to add this
> functionality.
--
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
