[gpfsug-discuss] Immutable fileset features

[Simon Thompson (Research Computing - IT Services)]

On 19/07/2015 13:45, "Frank Kraemer" <kraemerf at de.ibm.com> wrote:

>>I was wondering if anyone had looked at the immutable fileset features in
>4.1.1?
>
>yes, Nils Haustein has see:
>
>https://www.ibm.com/developerworks/community/blogs/storageneers/entry/Insi
>ght_to_the_IBM_Spectrum_Scale_GPFS_Immutability_function


I was re-reading some of this blog post and am a little confused.

It talks about setting retention times by setting the ATIME from touch, or
by using -E to mmchattr.

Does that mean if a file is accessed, then the ATIME is updated and so the
retention period is changed?

What if our retention policy is based on last access time of file +period
of time. I was thinking it would be useful to do a policy scan to find
newly access files and then set the retention (either directly by policy
if possible? Or by passing the file list to a script). Would this work or
if the ATIME is overloaded, then I guess we can¹t use this?

Finally, is this a feature that is supported by IBM?

The -E flag for mmchattr is neither in the man page nor the online docs at:
http://www-01.ibm.com/support/knowledgecenter/#!/STXKQY_4.1.1/com.ibm.spect
rum.scale.v4r11.adm.doc/bl1adm_mmchattr.htm

(My possibly incorrect understanding was that if its documented, then is
supported, otherwise it might work)?

Simon