[
https://issues.apache.org/jira/browse/HDFS-2246?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13152202#comment-13152202
]
Jitendra Nath Pandey commented on HDFS-2246:
--------------------------------------------
{quote}
Rather than a single user for the local path access, why not use an ACL,
given we already have support for parsing/checking ACLs? I can imagine some
people may have multiple applications that do local random-read access that
could benefit from this.
{quote}
The ACLs are configured for a protocol so we need to add a protocol just for
getBlockLocalPathInfo, which seems a bit overkill because the protocol will be
too specific to this special optimization.
{quote}
The cached proxies to the local DN currently don't have the UGI as part of
the key. So if a client needs to impersonate different users, the cache will
end up caching client proxies associated with previous users, which would be
incorrect.
{quote}
In this patch short circuit can't be used with impersonation because we check
for authentication method as KERBEROS at the datanode. In case of impersonation
the auth-method would be PROXY.
However, we will have to do that once we enable short circuit for multiple
users.
Is it ok if I address the ACL configuration and ugi in cache keys in a separate
jira for trunk and let 20s support only one user?
> Shortcut a local client reads to a Datanodes files directly
> -----------------------------------------------------------
>
> Key: HDFS-2246
> URL: https://issues.apache.org/jira/browse/HDFS-2246
> Project: Hadoop HDFS
> Issue Type: Improvement
> Reporter: Sanjay Radia
> Attachments: 0001-HDFS-347.-Local-reads.patch,
> HDFS-2246-branch-0.20-security-205.1.patch,
> HDFS-2246-branch-0.20-security-205.2.patch,
> HDFS-2246-branch-0.20-security-205.patch,
> HDFS-2246-branch-0.20-security-205.patch,
> HDFS-2246-branch-0.20-security-205.patch,
> HDFS-2246-branch-0.20-security.3.patch,
> HDFS-2246-branch-0.20-security.no-softref.patch,
> HDFS-2246-branch-0.20-security.patch, HDFS-2246-branch-0.20-security.patch,
> HDFS-2246-branch-0.20-security.patch, HDFS-2246-trunk.patch,
> HDFS-2246-trunk.patch, HDFS-2246.20s.1.patch, HDFS-2246.20s.2.txt,
> HDFS-2246.20s.3.txt, HDFS-2246.20s.4.txt, HDFS-2246.20s.patch,
> TestShortCircuitLocalRead.java, localReadShortcut20-security.2patch
>
>
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators:
https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira
