python-ldap says "Critical extension is unavailable" and "Internal (implementation specific) error"

[Ingo Steuwer <steuwer@univention.de>]

Hello

we are using python2.3 ldap-modules (which are using openldap-libs) to
import several informations (Users, Groups and surounding structure)
into openldap 2.1.30. To speed up on the dual-cpu-system we import in
two parallel instances. Because there are many entries to import (~90000
dns) the whole process takes about 30 hours.

After running about 26 hours without problems we're getting on some
changes the following errors:

Critical extension is unavailable

and later also

Internal (implementation specific) error

I can't find informations about them, does anybody know under what
conditions they appear ?

The script can make further modifications in the ldap, but some time
later accessing the ldap failes completely with "ldap-server BUSY" and
so no more modifications are possible.

At all time a ldapsearch is possible.

Is there a limit in openldap about time/connection oder
number-of-changes/connection ? Can I prevent such errors by reconnect
each 1000 changes (for example) ?

Thanks for any hints !

Ingo Steuwer

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