[ 
https://issues.apache.org/jira/browse/HADOOP-13081?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15507759#comment-15507759
 ] 

Sergey Shelukhin commented on HADOOP-13081:
-------------------------------------------

[~cnauroth] the concrete use case is where a service runs multiple pieces of 
work on behalf of users; it can be set to log in as a particular user using 
Kerberos, but the users can also add their own tokens.
We cannot add tokens to a single kerberos-based UGI because they will all mix; 
we also cannot log in for every piece of work in most cases, as it would 
overload the KDC.
Ideally, we should be able to reuse the kerberos login and create a separate 
UGI with it for each user, adding the user-specific tokens.

> add the ability to create multiple UGIs/subjects from one kerberos login
> ------------------------------------------------------------------------
>
>                 Key: HADOOP-13081
>                 URL: https://issues.apache.org/jira/browse/HADOOP-13081
>             Project: Hadoop Common
>          Issue Type: Improvement
>          Components: security
>            Reporter: Sergey Shelukhin
>            Assignee: Sergey Shelukhin
>             Fix For: 2.8.0, 3.0.0-alpha1
>
>         Attachments: HADOOP-13081.01.patch, HADOOP-13081.02.patch, 
> HADOOP-13081.02.patch, HADOOP-13081.03.patch, HADOOP-13081.03.patch, 
> HADOOP-13081.patch
>
>
> We have a scenario where we log in with kerberos as a certain user for some 
> tasks, but also want to add tokens to the resulting UGI that would be 
> specific to each task. We don't want to authenticate with kerberos for every 
> task.
> I am not sure how this can be accomplished with the existing UGI interface. 
> Perhaps some clone method would be helpful, similar to createProxyUser minus 
> the proxy stuff; or it could just relogin anew from ticket cache. 
> getUGIFromTicketCache seems like the best option in existing code, but there 
> doesn't appear to be a consistent way of handling ticket cache location - the 
> above method, that I only see called in test, is using a config setting that 
> is not used anywhere else, and the env variable for the location that is used 
> in the main ticket cache related methods is not set uniformly on all paths - 
> therefore, trying to find the correct ticket cache and passing it via the 
> config setting to getUGIFromTicketCache seems even hackier than doing the 
> clone via reflection ;) Moreover, getUGIFromTicketCache ignores the user 
> parameter on the main path - it logs a warning for multiple principals and 
> then logs in with first available.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

---------------------------------------------------------------------
To unsubscribe, e-mail: common-issues-unsubscr...@hadoop.apache.org
For additional commands, e-mail: common-issues-h...@hadoop.apache.org

Reply via email to