[PATCH] do a partial replication with drs replicate --local

[Stefan Metzmacher]

Hi Bob,

no the logic is not ok yet.

Am 08.02.2017 um 02:01 schrieb Bob Campbell:
>  
> -
>      source_dsa_invocation_id = misc.GUID(self.samdb.get_invocation_id())
>      dest_dsa_invocation_id = misc.GUID(self.local_samdb.get_invocation_id())
>      destination_dsa_guid = self.ntds_guid
>  
> +    # If we can't find an upToDateVector, replicate fully
> +    hwm = drsuapi.DsReplicaHighWaterMark()
> +    hwm.tmp_highest_usn = 0
> +    hwm.reserved_usn = 0
> +    hwm.highest_usn = 0
> +
> +    udv = None
> +    if not full_sync:
> +        res = self.local_samdb.search(base=NC, scope=ldb.SCOPE_BASE,
> +                                      attrs=["replUpToDateVector", "repsFrom"])
> +        if "repsFrom" in res[0]:
> +            for reps_from_packed in res[0]["repsFrom"]:
> +                reps_from_obj = ndr_unpack(drsblobs.repsFromToBlob, reps_from_packed)
> +                if reps_from_obj.ctr.source_dsa_invocation_id == source_dsa_invocation_id:
> +                    hwm = reps_from_obj.ctr.highwatermark
> +
> +        if "replUpToDateVector" in res[0]:
> +            udv_packed = res[0]["replUpToDateVector"][0]
> +            udv_obj = ndr_unpack(drsblobs.replUpToDateVectorBlob, udv_packed)
> +            udv_ctr = udv_obj.ctr
> +
> +            udv = drsuapi.DsReplicaCursorCtrEx()
> +            udv.version = 2
> +            udv.reserved1 = 0
> +            udv.reserved2 = 0
> +            cursors = []
> +
> +            highest_usn = self.local_samdb.sequence_number(ldb.SEQ_NEXT)
> +            found = False
> +            for cursor in udv_ctr.cursors:
> +                udv_ex_cursor = drsuapi.DsReplicaCursor()
> +                udv_ex_cursor.source_dsa_invocation_id = cursor.source_dsa_invocation_id
> +                udv_ex_cursor.highest_usn = cursor.highest_usn
> +                # Update the cursor if it's ours
> +                if cursor.source_dsa_invocation_id == source_dsa_invocation_id:
> +                    udv_ex_cursor.highest_usn = highest_usn
> +                    found = True
> +                cursors.append(udv_ex_cursor)
> +
> +            # If we didn't find our cursor, add a new one for us
> +            if not found:
> +                our_udv_cursor = drsuapi.DsReplicaCursor()
> +                our_udv_cursor.source_dsa_invocation_id = source_dsa_invocation_id
> +                our_udv_cursor.highest_usn = highest_usn
> +                cursors.append(our_udv_cursor)
> +
> +            udv.cursors = cursors
> +            udv.count = len(cursors)
> +

It needs to be something like this:


    highest_usn = self.local_samdb.sequence_number(ldb.SEQ_NEXT)

    # If we can't find an upToDateVector, replicate fully
    hwm = drsuapi.DsReplicaHighWaterMark()
    hwm.tmp_highest_usn = 0
    hwm.reserved_usn = 0
    hwm.highest_usn = 0

    udv = None
    if not full_sync:
        res = self.local_samdb.search(base=NC, scope=ldb.SCOPE_BASE,
                                      attrs=["replUpToDateVector",
"repsFrom"])
        if "repsFrom" in res[0]:
            for reps_from_packed in res[0]["repsFrom"]:
                reps_from_obj = ndr_unpack(drsblobs.repsFromToBlob,
reps_from_packed)
                if reps_from_obj.ctr.source_dsa_invocation_id ==
source_dsa_invocation_id:
                    hwm = reps_from_obj.ctr.highwatermark

        # The following logic should match dsdb_load_udv_v2()!
        cursors = []
        found = False

        if "replUpToDateVector" in res[0]:
            udv_packed = res[0]["replUpToDateVector"][0]
            udv_obj = ndr_unpack(drsblobs.replUpToDateVectorBlob,
udv_packed)
            udv_ctr = udv_obj.ctr

            for cursor in udv_ctr.cursors:
                udv_ex_cursor = drsuapi.DsReplicaCursor()
                udv_ex_cursor.source_dsa_invocation_id =
cursor.source_dsa_invocation_id
                # Update the cursor if it's ours
                if cursor.source_dsa_invocation_id ==
destinatoin_dsa_invocation_id:
                    udv_ex_cursor.highest_usn = highest_usn
                    found = True
                else:
                    udv_ex_cursor.highest_usn = cursor.highest_usn
                cursors.append(udv_ex_cursor)

        # If we didn't find our cursor, add a new one for us
        if not found:
            our_udv_cursor = drsuapi.DsReplicaCursor()
            our_udv_cursor.source_dsa_invocation_id =
destination_dsa_invocation_id
            our_udv_cursor.highest_usn = highest_usn
            cursors.append(our_udv_cursor)

        todo_sort_by_guid(cursors)

        udv = drsuapi.DsReplicaCursorCtrEx()
        udv.version = 2
        udv.reserved1 = 0
        udv.reserved2 = 0
        udv.cursors = cursors
        udv.count = len(cursors)

The main points are that our highest_usn belongs to our
destination_dsa_invocation_id not to the source_dsa_invocation_id variable.
and we need to create the udv even without "replUpToDateVector" in that
case we just send our own cursor.

And you should to sort the cursors at the end see:
TYPESAFE_QSORT(*cursors, *count, drsuapi_DsReplicaCursor2_compare);

Another approach would be to add python bindings for dsdb_load_udv_v2().

metze

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