[gpfsug-discuss] Mapping GPFS v5 Windows client to same UID...?
IBM Spectrum Scale
scale at us.ibm.com
Tue Feb 5 20:09:07 GMT 2019
What you are seeing has to do with whether UAC (User Access Control) is
enabled/disabled on Windows.
On Windows 7 and 2012R2 etc, my guess is that you have disabled UAC (since
that is what GPFS required in the past). When UAC is disabled, the default
owner of a local file/dir created by a user that is member of
Administrators group, is set as Administrators (SID = S-1-5-32-544). That
is mapped to autogenerated-id 15,000,000 in your case. On Windows 10
(where UAC MUST stay enabled), the behavior changes. When UAC is not
disabled (and NOT running elevated), the default owner of a local file/dir
created by a user that is member of Administrators group, is set to that
user SID. Hence, it is not S-1-5-32-544, rather a unique SID for that
local user. In absence of AD setup and RFC 2307 mappings, GPFS is
auto-mapping that user SID to 15,000, 270 in your case. As you see, the
state of UAC results in different owners.
You simply cannot disable UAC on Windows 10 (and newer versions) since it
breaks certain OS components! Hence, to get consistent behavior (the
latter semantics where file owner = user SID), you could enable UAC on
Windows 7/2012R2 to default (instead of disabling it). GPFS 126.96.36.199 works
with UAC enabled. Remember though that the old 15,000,000 is on-disk ACL
structures, hence you will have to explicitly set/change owner to yourself
(to update to 15,000,270) for existing files. Any new files/dirs though
should default to 15,000,270.
You could also add an ACL entry for Administrators group or individual
users granting desired access instead of relying on file ownership for
Regards, The Spectrum Scale (GPFS) team
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From: "Henrik Cednert (Filmlance)" <henrik.cednert at filmlance.se>
To: gpfsug main discussion list <gpfsug-discuss at spectrumscale.org>
Date: 02/05/2019 11:21 AM
Subject: [gpfsug-discuss] Mapping GPFS v5 Windows client to same
Sent by: gpfsug-discuss-bounces at spectrumscale.org
Odd. Apparently i have issues posting to the list again. Sorry if this
comes in double.
I’ve read a bit about this on the net but can’t wrap my tiny little brain
We have a bunch of windows 7 and 2012r2 clients that ran v4 previously.
After a system/server upgrade of the DDN Mediascaler to 188.8.131.52 we had to
upgrade those clients to v5 so that they're compatible. In addition to
that a new v5 windows 10 client was deployed.
The old windows 7 and 2012r2 clients writes to the system with the same
UID, 15000000, but unique GID. The new client has its UID set to 12000270
and an unique GID. This cases all sorts of painful verbal and non verblam
Funny thing is that a newly added 2012r2 windows client has UID 15000000,
so it’s just the windows 10 client that messes with me. All have been
installed with same installers and same procedures.
Since all the others can write with same UID this new windows 10 one for
sure has to be able to do it as well. Or? Can someone please point me in
the right direction here?
Yes, I know an AD is best practice. But not possible at the moment so I’d
just like to restore the same functionality that we had before upgrade.
Cheers and thanks.
Henrik Cednert / + 46 704 71 89 54 / CTO / Filmlance
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