Consistent ID mapping

miguel.sanders at miguel.sanders at
Tue May 12 06:58:13 GMT 2009

Hi Volker

Well the TDB files are not on the GPFS filesystem. Besides ID mapping, is this mandatory to put this on the GPFS filesystem?
I have been looking at the idmap_rid but afaik that's only valid in a single AD domain configuration. (I have multiple...)

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-----Oorspronkelijk bericht-----
Van: Volker Lendecke [mailto:Volker.Lendecke at SerNet.DE] 
Verzonden: maandag 11 mei 2009 22:14
Aan: SANDERS Miguel
CC: samba-technical at
Onderwerp: Re: Consistent ID mapping

On Mon, May 11, 2009 at 09:30:11PM +0200, miguel.sanders at wrote:
> I have a question on how to keep ID mapping consistent.(my Samba 
> backend is a GPFS filesystem).

You're certainly using samba+ctdb? Everything else will lead to data corruption sooner or later.

> My main concern now is that the SID to UID/GID mapping should be 
> consistent over the cluster nodes in order to keep ACLs consistent.  
> Any pointers on how can I achieve that?

Different possibilities. With idmap_tdb2 and ctdb you will put the idmap.tdb into a persistent tdb file which is consistent across the cluster. Alternatively you can use idmap_rid or idmap_ad (assuming you have SFU) which automatically keep the ID mappings consistent.


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