Re: Correct way to load LDIF in mirrormode

[masarati@aero.polimi.it]

> On Sun, Nov 22, 2009 at 5:42 AM, Howard Chu <hyc@symas.com> wrote:> but it
> will only write related data if (update_ctxcsn)
>
>>
>> The manpage clearly states that -S sets the SID used in generated
>> entryCSNs.
>>
>> It also clearly states that the -w option writes the contextCSN based on
>> the
>> greatest entryCSN in the database.
>>
>> Period, end of story.
>>
>
> Indeed.
>
> So the consequence is that the -S <sid> option is used to initialize the
> entryCSN's, regardless of if the -w option being provided.
>
> If the -w option is provided, then the entryCSN's are searched for the
> maximal entryCSN, which becomes the contextCSN (either recently generated,
> or provided as part of the LDIF being loaded)
>
> If the -S is not provided, it defaults to 0.

Just to clarify (your first statement sounds a bit ambiguous to me): -w
and -S are sort of orthogonal.

If the database has "lastmod on", slapadd adds entryCSN (and entryUUID,
and createTimestamp, modifyTimestamp and so) unless already present in the
LDIF.  Already present values are left untouched.

The entryCSN is generated using the SID passed with -S; it defaults to 0.

When -w is used, the largest entryCSN for each independent SID is
collected, regardless of being generated or already present in the LDIF,
and written in the contextCSN (as soon as slapadd's execution is
successful, of course).  The contextCSN is multi-valued.

So, for example, an LDIF like this (skipping unnecessary details)

dn: dc=example,dc=com
entryCSN: 20091122093849.380000Z#000000#000#000000

dn: ou=People,dc=example,dc=com
entryCSN: 20091122093850.380000Z#000000#001#000000

dn: ou=Groups,dc=example,dc=com
entryCSN: 20091122093851.380000Z#000000#002#000000

dn: cn=Someone,ou=People,dc=example,dc=com
# no entryCSN

run with slapadd -w -S 3 will result in

dn: dc=example,dc=com
entryCSN: 20091122093849.380000Z#000000#000#000000
# gathered by slapadd run with -w
contextCSN: 20091122093849.380000Z#000000#000#000000
contextCSN: 20091122093850.380000Z#000000#001#000000
contextCSN: 20091122093851.380000Z#000000#002#000000
contextCSN: 20091122093852.380000Z#000000#003#000000

dn: ou=People,dc=example,dc=com
entryCSN: 20091122093850.380000Z#000000#001#000000

dn: ou=Groups,dc=example,dc=com
entryCSN: 20091122093851.380000Z#000000#002#000000

dn: cn=Someone,ou=People,dc=example,dc=com
# added by slapadd, with SID=3 as passed by -S 3
entryCSN: 20091122093852.380000Z#000000#003#000000

Hope this clarifies.  Feel free to turn this into a FAQ entry, or better
an example for the Admin Guide :)

p.