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https://issues.apache.org/jira/browse/MESOS-6818?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15763184#comment-15763184
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Anindya Sinha commented on MESOS-6818:
--------------------------------------

To handle this case, we can determine if disks are empty or not at agent 
startup and looking at the contents of the checkpoint info at that time. If 
there is a disk that contains old data, there are 2 approaches that can be done:

a) Do not allow the agent to register with the master. It would therefore 
require an operator to clean/format the disk (or change the static resources 
pertaining to these unclean disks.
b) Allow the agent to register with disks that have clean contents only. Say, 
the --resources flag indicates 4 disks of which 1 of the disk is unclean (i.e. 
old data exists), the agent advertises only 3 disks as available resources.


> Ensure empty contents in persistent volume if disk not in use.
> --------------------------------------------------------------
>
>                 Key: MESOS-6818
>                 URL: https://issues.apache.org/jira/browse/MESOS-6818
>             Project: Mesos
>          Issue Type: Improvement
>          Components: general
>            Reporter: Anindya Sinha
>            Priority: Minor
>              Labels: persistent-volumes
>
> Currently, when a persistent volume is DESTROYed, we ensure that `rmdir` of 
> that directory is successful before returning that disk as an offereable 
> resource. So, when a CREATE is received for the same path, we thereby ensure 
> that the contents of that path is empty (MOUNT disks will have the root 
> present though). This ensures that frameworks of the same role do not leak 
> content to other frameworks. Reference: MESOS-5448.
> However, an agent might join a cluster who do not have the path corresponding 
> to the disks clean. One of the scenarios might be if the agents join a new 
> cluster after being repurposed from another cluster without their disks being 
> formatted. In such a case, the CREATE of a persistent volume on an existing 
> path might contain data left over from a previous run in the old cluster 
> which might lead to inconsistencies esp if the tasks running in the container 
> *always* expect to receive a clean persistent volume.



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