[Samba] Samba4 syncpassword fails

[Jeremy Allison]

On Mon, Aug 17, 2020 at 06:44:53AM +0000, Julien TEHERY via samba wrote:
> >Well, I ask myself the same question. The fact is that it went bad at the precise second we tried to add a new remote DC to the domain.
> >This never happened before has we had many other remote DCs and use to join them whitout any problem.
> >
> >I was hopping that deleting and recreating the ldb cache would be sufficient, but it wasn't. Launching the daemonized script failed at the end of the first sync with the error i gave you.
> 
> 
> Is anyone on the dev side able to explain what happens here?
> 
> Reminder of the error during a password sync:
> 
> Thu Aug 13 15:19:12 2020: pid[31990]: ldb.LdbError(12) => (LDAP error 12 LDAP_UNAVAILABLE_CRITICAL_EXTENSION -  <0000202C: Unable to unmarshall cookie as a ldapControlDirSyncCookie structure at ../source4/dsdb/samdb/ldb_modules/dirsync.c:1269> <>)

This function ndr_pull_ldapControlDirSyncCookie()
returned an error. Add debug output and drill down
into what it is failing to parse.