rhatguy1

updated

10 years ago

R

rhatguy1

6 Posts

0

2716

April 13th, 2017 20:00

Cloud tier data movement

Is there any way to force a DD cloud tiering policy to move data younger than 14 days old even for POC purposes?  I want to just move everything for a POC.

  • James_Ford

    30 Posts

    1994

    1

    Posted April 19th, 2017 13:00

    Hi,

    A couple of points around this:

    - The smallest data movement policy you can set against an mtree is 14 days

    - Files are selected for migration when data movement runs if (current time - file modification time) > data movement policy for the mtree

    There is no way in which customers can override the 14 day minimum so only files which have 'aged' > 14 days can be migrated from active tier -> cloud/object storage. As a result of this the only way to migrate newly written data is to manually set the files modification time (mtime) to a previous point in time.

    A files mtime can be modified using the unix/linux touch command - for example I create a new file:

    # ls -al /data/col1/jftest/testfile

    -rw-r--r--  1 root root 10737418240 Feb 23 16:38 /data/col1/jftest/testfile

    I move the files mtime back by 90 days using the touch command:

    # touch -d '90 days ago' /data/col1/jftest/testfile

    We can see that the mtime has changed as follows:

    # ls -al /data/col1/jftest/testfile

    -rw-r--r--  1 root root 10737418240 Dec 15 17:00 /data/col1/jftest/testfile

    Even if this file were brand new it would now be migrated if the corresponding mtree had a migration policy of 90 days.

    When working with files on a DDR you can change the mtime using touch from a unix/linux system via an NFS mount or from a Windows system using a CIFS share (assuming you have touch.exe installed on the Windows system).

    Hopefully this helps?

    Thanks, James

  • rhatguy1

    6 Posts

    1994

    0

    Posted April 19th, 2017 16:00

    This is what I was looking for.  Thanks!